wp/wp-admin/js/updates.js
changeset 7 cf61fcea0001
parent 5 5e2f62d02dcd
child 9 177826044cd9
--- a/wp/wp-admin/js/updates.js	Tue Jun 09 11:14:17 2015 +0000
+++ b/wp/wp-admin/js/updates.js	Mon Oct 14 17:39:30 2019 +0200
@@ -1,7 +1,45 @@
-/* global tb_remove */
-window.wp = window.wp || {};
+/**
+ * Functions for ajaxified updates, deletions and installs inside the WordPress admin.
+ *
+ * @version 4.2.0
+ *
+ * @package WordPress
+ * @subpackage Administration
+ */
+
+/* global pagenow */
 
-(function( $, wp, pagenow ) {
+/**
+ * @param {jQuery}  $                                   jQuery object.
+ * @param {object}  wp                                  WP object.
+ * @param {object}  settings                            WP Updates settings.
+ * @param {string}  settings.ajax_nonce                 AJAX nonce.
+ * @param {object}  settings.l10n                       Translation strings.
+ * @param {object=} settings.plugins                    Base names of plugins in their different states.
+ * @param {Array}   settings.plugins.all                Base names of all plugins.
+ * @param {Array}   settings.plugins.active             Base names of active plugins.
+ * @param {Array}   settings.plugins.inactive           Base names of inactive plugins.
+ * @param {Array}   settings.plugins.upgrade            Base names of plugins with updates available.
+ * @param {Array}   settings.plugins.recently_activated Base names of recently activated plugins.
+ * @param {object=} settings.themes                     Plugin/theme status information or null.
+ * @param {number}  settings.themes.all                 Amount of all themes.
+ * @param {number}  settings.themes.upgrade             Amount of themes with updates available.
+ * @param {number}  settings.themes.disabled            Amount of disabled themes.
+ * @param {object=} settings.totals                     Combined information for available update counts.
+ * @param {number}  settings.totals.count               Holds the amount of available updates.
+ */
+(function( $, wp, settings ) {
+	var $document = $( document );
+
+	wp = wp || {};
+
+	/**
+	 * The WP Updates object.
+	 *
+	 * @since 4.2.0
+	 *
+	 * @type {object}
+	 */
 	wp.updates = {};
 
 	/**
@@ -9,545 +47,2434 @@
 	 *
 	 * @since 4.2.0
 	 *
-	 * @var string
+	 * @type {string}
 	 */
-	wp.updates.ajaxNonce = window._wpUpdatesSettings.ajax_nonce;
+	wp.updates.ajaxNonce = settings.ajax_nonce;
 
 	/**
 	 * Localized strings.
 	 *
 	 * @since 4.2.0
 	 *
-	 * @var object
+	 * @type {object}
 	 */
-	wp.updates.l10n = window._wpUpdatesSettings.l10n;
+	wp.updates.l10n = settings.l10n;
+
+	/**
+	 * Current search term.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @type {string}
+	 */
+	wp.updates.searchTerm = '';
 
 	/**
 	 * Whether filesystem credentials need to be requested from the user.
 	 *
 	 * @since 4.2.0
 	 *
-	 * @var bool
+	 * @type {bool}
 	 */
-	wp.updates.shouldRequestFilesystemCredentials = null;
+	wp.updates.shouldRequestFilesystemCredentials = false;
 
 	/**
 	 * Filesystem credentials to be packaged along with the request.
 	 *
 	 * @since 4.2.0
+	 * @since 4.6.0 Added `available` property to indicate whether credentials have been provided.
 	 *
-	 * @var object
+	 * @type {object} filesystemCredentials                    Holds filesystem credentials.
+	 * @type {object} filesystemCredentials.ftp                Holds FTP credentials.
+	 * @type {string} filesystemCredentials.ftp.host           FTP host. Default empty string.
+	 * @type {string} filesystemCredentials.ftp.username       FTP user name. Default empty string.
+	 * @type {string} filesystemCredentials.ftp.password       FTP password. Default empty string.
+	 * @type {string} filesystemCredentials.ftp.connectionType Type of FTP connection. 'ssh', 'ftp', or 'ftps'.
+	 *                                                         Default empty string.
+	 * @type {object} filesystemCredentials.ssh                Holds SSH credentials.
+	 * @type {string} filesystemCredentials.ssh.publicKey      The public key. Default empty string.
+	 * @type {string} filesystemCredentials.ssh.privateKey     The private key. Default empty string.
+	 * @type {string} filesystemCredentials.fsNonce            Filesystem credentials form nonce.
+	 * @type {bool}   filesystemCredentials.available          Whether filesystem credentials have been provided.
+	 *                                                         Default 'false'.
 	 */
 	wp.updates.filesystemCredentials = {
-		ftp: {
-			host: null,
-			username: null,
-			password: null,
-			connectionType: null
+		ftp:       {
+			host:           '',
+			username:       '',
+			password:       '',
+			connectionType: ''
 		},
-		ssh: {
-			publicKey: null,
-			privateKey: null
-		}
+		ssh:       {
+			publicKey:  '',
+			privateKey: ''
+		},
+		fsNonce: '',
+		available: false
 	};
 
 	/**
-	 * Flag if we're waiting for an update to complete.
+	 * Whether we're waiting for an Ajax request to complete.
 	 *
 	 * @since 4.2.0
+	 * @since 4.6.0 More accurately named `ajaxLocked`.
 	 *
-	 * @var bool
+	 * @type {bool}
 	 */
-	wp.updates.updateLock = false;
+	wp.updates.ajaxLocked = false;
 
 	/**
-	 * * Flag if we've done an update successfully.
+	 * Admin notice template.
 	 *
-	 * @since 4.2.0
+	 * @since 4.6.0
 	 *
-	 * @var bool
+	 * @type {function} A function that lazily-compiles the template requested.
 	 */
-	wp.updates.updateDoneSuccessfully = false;
+	wp.updates.adminNotice = wp.template( 'wp-updates-admin-notice' );
 
 	/**
+	 * Update queue.
+	 *
 	 * If the user tries to update a plugin while an update is
 	 * already happening, it can be placed in this queue to perform later.
 	 *
 	 * @since 4.2.0
+	 * @since 4.6.0 More accurately named `queue`.
 	 *
-	 * @var array
+	 * @type {Array.object}
 	 */
-	wp.updates.updateQueue = [];
+	wp.updates.queue = [];
 
 	/**
-	 * Store a jQuery reference to return focus to when exiting the request credentials modal.
+	 * Holds a jQuery reference to return focus to when exiting the request credentials modal.
 	 *
 	 * @since 4.2.0
 	 *
-	 * @var jQuery object
+	 * @type {jQuery}
 	 */
-	wp.updates.$elToReturnFocusToFromCredentialsModal = null;
+	wp.updates.$elToReturnFocusToFromCredentialsModal = undefined;
 
 	/**
-	 * Decrement update counts throughout the various menus.
+	 * Adds or updates an admin notice.
+	 *
+	 * @since 4.6.0
 	 *
-	 * @since 3.9.0
+	 * @param {object}  data
+	 * @param {*=}      data.selector      Optional. Selector of an element to be replaced with the admin notice.
+	 * @param {string=} data.id            Optional. Unique id that will be used as the notice's id attribute.
+	 * @param {string=} data.className     Optional. Class names that will be used in the admin notice.
+	 * @param {string=} data.message       Optional. The message displayed in the notice.
+	 * @param {number=} data.successes     Optional. The amount of successful operations.
+	 * @param {number=} data.errors        Optional. The amount of failed operations.
+	 * @param {Array=}  data.errorMessages Optional. Error messages of failed operations.
 	 *
-	 * @param {string} updateType
 	 */
-	wp.updates.decrementCount = function( upgradeType ) {
-		var count,
-			pluginCount,
-			$adminBarUpdateCount = $( '#wp-admin-bar-updates .ab-label' ),
-			$dashboardNavMenuUpdateCount = $( 'a[href="update-core.php"] .update-plugins' ),
-			$pluginsMenuItem = $( '#menu-plugins' );
-
-
-		count = $adminBarUpdateCount.text();
-		count = parseInt( count, 10 ) - 1;
-		if ( count < 0 || isNaN( count ) ) {
-			return;
-		}
-		$( '#wp-admin-bar-updates .ab-item' ).removeAttr( 'title' );
-		$adminBarUpdateCount.text( count );
+	wp.updates.addAdminNotice = function( data ) {
+		var $notice = $( data.selector ), $adminNotice;
 
+		delete data.selector;
+		$adminNotice = wp.updates.adminNotice( data );
 
-		$dashboardNavMenuUpdateCount.each( function( index, elem ) {
-			elem.className = elem.className.replace( /count-\d+/, 'count-' + count );
-		} );
-		$dashboardNavMenuUpdateCount.removeAttr( 'title' );
-		$dashboardNavMenuUpdateCount.find( '.update-count' ).text( count );
+		// Check if this admin notice already exists.
+		if ( ! $notice.length ) {
+			$notice = $( '#' + data.id );
+		}
 
-		if ( 'plugin' === upgradeType ) {
-			pluginCount = $pluginsMenuItem.find( '.plugin-count' ).eq(0).text();
-			pluginCount = parseInt( pluginCount, 10 ) - 1;
-			if ( pluginCount < 0 || isNaN( pluginCount ) ) {
-				return;
-			}
-			$pluginsMenuItem.find( '.plugin-count' ).text( pluginCount );
-			$pluginsMenuItem.find( '.update-plugins' ).each( function( index, elem ) {
-				elem.className = elem.className.replace( /count-\d+/, 'count-' + pluginCount );
-			} );
-
-			if (pluginCount > 0 ) {
-				$( '.subsubsub .upgrade .count' ).text( '(' + pluginCount + ')' );
+		if ( $notice.length ) {
+			$notice.replaceWith( $adminNotice );
+		} else {
+			if ( 'customize' === pagenow ) {
+				$( '.customize-themes-notifications' ).append( $adminNotice );
 			} else {
-				$( '.subsubsub .upgrade' ).remove();
+				$( '.wrap' ).find( '> h1' ).after( $adminNotice );
 			}
 		}
+
+		$document.trigger( 'wp-updates-notice-added' );
 	};
 
 	/**
-	 * Send an Ajax request to the server to update a plugin.
+	 * Handles Ajax requests to WordPress.
+	 *
+	 * @since 4.6.0
 	 *
-	 * @since 4.2.0
-	 *
-	 * @param {string} plugin
-	 * @param {string} slug
+	 * @param {string} action The type of Ajax request ('update-plugin', 'install-theme', etc).
+	 * @param {object} data   Data that needs to be passed to the ajax callback.
+	 * @return {$.promise}    A jQuery promise that represents the request,
+	 *                        decorated with an abort() method.
 	 */
-	wp.updates.updatePlugin = function( plugin, slug ) {
-		var $message, name;
-		if ( 'plugins' === pagenow || 'plugins-network' === pagenow ) {
-			$message = $( '[data-slug="' + slug + '"]' ).next().find( '.update-message' );
-		} else if ( 'plugin-install' === pagenow ) {
-			$message = $( '.plugin-card-' + slug ).find( '.update-now' );
-			name = $message.data( 'name' );
-			$message.attr( 'aria-label', wp.updates.l10n.updatingLabel.replace( '%s', name ) );
+	wp.updates.ajax = function( action, data ) {
+		var options = {};
+
+		if ( wp.updates.ajaxLocked ) {
+			wp.updates.queue.push( {
+				action: action,
+				data:   data
+			} );
+
+			// Return a Deferred object so callbacks can always be registered.
+			return $.Deferred();
 		}
 
-		$message.addClass( 'updating-message' );
-		if ( $message.html() !== wp.updates.l10n.updating ){
-			$message.data( 'originaltext', $message.html() );
+		wp.updates.ajaxLocked = true;
+
+		if ( data.success ) {
+			options.success = data.success;
+			delete data.success;
 		}
 
-		$message.text( wp.updates.l10n.updating );
-		wp.a11y.speak( wp.updates.l10n.updatingMsg );
-
-		if ( wp.updates.updateLock ) {
-			wp.updates.updateQueue.push( {
-				type: 'update-plugin',
-				data: {
-					plugin: plugin,
-					slug: slug
-				}
-			} );
-			return;
+		if ( data.error ) {
+			options.error = data.error;
+			delete data.error;
 		}
 
-		wp.updates.updateLock = true;
-
-		var data = {
+		options.data = _.extend( data, {
+			action:          action,
 			_ajax_nonce:     wp.updates.ajaxNonce,
-			plugin:          plugin,
-			slug:            slug,
+			_fs_nonce:       wp.updates.filesystemCredentials.fsNonce,
 			username:        wp.updates.filesystemCredentials.ftp.username,
 			password:        wp.updates.filesystemCredentials.ftp.password,
 			hostname:        wp.updates.filesystemCredentials.ftp.hostname,
 			connection_type: wp.updates.filesystemCredentials.ftp.connectionType,
 			public_key:      wp.updates.filesystemCredentials.ssh.publicKey,
 			private_key:     wp.updates.filesystemCredentials.ssh.privateKey
-		};
+		} );
+
+		return wp.ajax.send( options ).always( wp.updates.ajaxAlways );
+	};
+
+	/**
+	 * Actions performed after every Ajax request.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @param {object}  response
+	 * @param {array=}  response.debug     Optional. Debug information.
+	 * @param {string=} response.errorCode Optional. Error code for an error that occurred.
+	 */
+	wp.updates.ajaxAlways = function( response ) {
+		if ( ! response.errorCode || 'unable_to_connect_to_filesystem' !== response.errorCode ) {
+			wp.updates.ajaxLocked = false;
+			wp.updates.queueChecker();
+		}
+
+		if ( 'undefined' !== typeof response.debug && window.console && window.console.log ) {
+			_.map( response.debug, function( message ) {
+				window.console.log( $( '<p />' ).html( message ).text() );
+			} );
+		}
+	};
+
+	/**
+	 * Refreshes update counts everywhere on the screen.
+	 *
+	 * @since 4.7.0
+	 */
+	wp.updates.refreshCount = function() {
+		var $adminBarUpdates              = $( '#wp-admin-bar-updates' ),
+			$dashboardNavMenuUpdateCount  = $( 'a[href="update-core.php"] .update-plugins' ),
+			$pluginsNavMenuUpdateCount    = $( 'a[href="plugins.php"] .update-plugins' ),
+			$appearanceNavMenuUpdateCount = $( 'a[href="themes.php"] .update-plugins' ),
+			itemCount;
+
+		$adminBarUpdates.find( '.ab-item' ).removeAttr( 'title' );
+		$adminBarUpdates.find( '.ab-label' ).text( settings.totals.counts.total );
+
+		// Remove the update count from the toolbar if it's zero.
+		if ( 0 === settings.totals.counts.total ) {
+			$adminBarUpdates.find( '.ab-label' ).parents( 'li' ).remove();
+		}
+
+		// Update the "Updates" menu item.
+		$dashboardNavMenuUpdateCount.each( function( index, element ) {
+			element.className = element.className.replace( /count-\d+/, 'count-' + settings.totals.counts.total );
+		} );
+		if ( settings.totals.counts.total > 0 ) {
+			$dashboardNavMenuUpdateCount.find( '.update-count' ).text( settings.totals.counts.total );
+		} else {
+			$dashboardNavMenuUpdateCount.remove();
+		}
+
+		// Update the "Plugins" menu item.
+		$pluginsNavMenuUpdateCount.each( function( index, element ) {
+			element.className = element.className.replace( /count-\d+/, 'count-' + settings.totals.counts.plugins );
+		} );
+		if ( settings.totals.counts.total > 0 ) {
+			$pluginsNavMenuUpdateCount.find( '.plugin-count' ).text( settings.totals.counts.plugins );
+		} else {
+			$pluginsNavMenuUpdateCount.remove();
+		}
+
+		// Update the "Appearance" menu item.
+		$appearanceNavMenuUpdateCount.each( function( index, element ) {
+			element.className = element.className.replace( /count-\d+/, 'count-' + settings.totals.counts.themes );
+		} );
+		if ( settings.totals.counts.total > 0 ) {
+			$appearanceNavMenuUpdateCount.find( '.theme-count' ).text( settings.totals.counts.themes );
+		} else {
+			$appearanceNavMenuUpdateCount.remove();
+		}
+
+		// Update list table filter navigation.
+		if ( 'plugins' === pagenow || 'plugins-network' === pagenow ) {
+			itemCount = settings.totals.counts.plugins;
+		} else if ( 'themes' === pagenow || 'themes-network' === pagenow ) {
+			itemCount = settings.totals.counts.themes;
+		}
+
+		if ( itemCount > 0 ) {
+			$( '.subsubsub .upgrade .count' ).text( '(' + itemCount + ')' );
+		} else {
+			$( '.subsubsub .upgrade' ).remove();
+			$( '.subsubsub li:last' ).html( function() { return $( this ).children(); } );
+		}
+	};
+
+	/**
+	 * Decrements the update counts throughout the various menus.
+	 *
+	 * This includes the toolbar, the "Updates" menu item and the menu items
+	 * for plugins and themes.
+	 *
+	 * @since 3.9.0
+	 *
+	 * @param {string} type The type of item that was updated or deleted.
+	 *                      Can be 'plugin', 'theme'.
+	 */
+	wp.updates.decrementCount = function( type ) {
+		settings.totals.counts.total = Math.max( --settings.totals.counts.total, 0 );
+
+		if ( 'plugin' === type ) {
+			settings.totals.counts.plugins = Math.max( --settings.totals.counts.plugins, 0 );
+		} else if ( 'theme' === type ) {
+			settings.totals.counts.themes = Math.max( --settings.totals.counts.themes, 0 );
+		}
+
+		wp.updates.refreshCount( type );
+	};
+
+	/**
+	 * Sends an Ajax request to the server to update a plugin.
+	 *
+	 * @since 4.2.0
+	 * @since 4.6.0 More accurately named `updatePlugin`.
+	 *
+	 * @param {object}               args         Arguments.
+	 * @param {string}               args.plugin  Plugin basename.
+	 * @param {string}               args.slug    Plugin slug.
+	 * @param {updatePluginSuccess=} args.success Optional. Success callback. Default: wp.updates.updatePluginSuccess
+	 * @param {updatePluginError=}   args.error   Optional. Error callback. Default: wp.updates.updatePluginError
+	 * @return {$.promise} A jQuery promise that represents the request,
+	 *                     decorated with an abort() method.
+	 */
+	wp.updates.updatePlugin = function( args ) {
+		var $updateRow, $card, $message, message;
+
+		args = _.extend( {
+			success: wp.updates.updatePluginSuccess,
+			error: wp.updates.updatePluginError
+		}, args );
+
+		if ( 'plugins' === pagenow || 'plugins-network' === pagenow ) {
+			$updateRow = $( 'tr[data-plugin="' + args.plugin + '"]' );
+			$message   = $updateRow.find( '.update-message' ).removeClass( 'notice-error' ).addClass( 'updating-message notice-warning' ).find( 'p' );
+			message    = wp.updates.l10n.pluginUpdatingLabel.replace( '%s', $updateRow.find( '.plugin-title strong' ).text() );
+		} else if ( 'plugin-install' === pagenow || 'plugin-install-network' === pagenow ) {
+			$card    = $( '.plugin-card-' + args.slug );
+			$message = $card.find( '.update-now' ).addClass( 'updating-message' );
+			message  = wp.updates.l10n.pluginUpdatingLabel.replace( '%s', $message.data( 'name' ) );
+
+			// Remove previous error messages, if any.
+			$card.removeClass( 'plugin-card-update-failed' ).find( '.notice.notice-error' ).remove();
+		}
+
+		if ( $message.html() !== wp.updates.l10n.updating ) {
+			$message.data( 'originaltext', $message.html() );
+		}
+
+		$message
+			.attr( 'aria-label', message )
+			.text( wp.updates.l10n.updating );
+
+		$document.trigger( 'wp-plugin-updating', args );
+
+		return wp.updates.ajax( 'update-plugin', args );
+	};
+
+	/**
+	 * Updates the UI appropriately after a successful plugin update.
+	 *
+	 * @since 4.2.0
+	 * @since 4.6.0 More accurately named `updatePluginSuccess`.
+	 *
+	 * @typedef {object} updatePluginSuccess
+	 * @param {object} response            Response from the server.
+	 * @param {string} response.slug       Slug of the plugin to be updated.
+	 * @param {string} response.plugin     Basename of the plugin to be updated.
+	 * @param {string} response.pluginName Name of the plugin to be updated.
+	 * @param {string} response.oldVersion Old version of the plugin.
+	 * @param {string} response.newVersion New version of the plugin.
+	 */
+	wp.updates.updatePluginSuccess = function( response ) {
+		var $pluginRow, $updateMessage, newText;
+
+		if ( 'plugins' === pagenow || 'plugins-network' === pagenow ) {
+			$pluginRow     = $( 'tr[data-plugin="' + response.plugin + '"]' )
+				.removeClass( 'update' )
+				.addClass( 'updated' );
+			$updateMessage = $pluginRow.find( '.update-message' )
+				.removeClass( 'updating-message notice-warning' )
+				.addClass( 'updated-message notice-success' ).find( 'p' );
+
+			// Update the version number in the row.
+			newText = $pluginRow.find( '.plugin-version-author-uri' ).html().replace( response.oldVersion, response.newVersion );
+			$pluginRow.find( '.plugin-version-author-uri' ).html( newText );
+		} else if ( 'plugin-install' === pagenow || 'plugin-install-network' === pagenow ) {
+			$updateMessage = $( '.plugin-card-' + response.slug ).find( '.update-now' )
+				.removeClass( 'updating-message' )
+				.addClass( 'button-disabled updated-message' );
+		}
+
+		$updateMessage
+			.attr( 'aria-label', wp.updates.l10n.pluginUpdatedLabel.replace( '%s', response.pluginName ) )
+			.text( wp.updates.l10n.pluginUpdated );
+
+		wp.a11y.speak( wp.updates.l10n.updatedMsg, 'polite' );
+
+		wp.updates.decrementCount( 'plugin' );
+
+		$document.trigger( 'wp-plugin-update-success', response );
+	};
+
+	/**
+	 * Updates the UI appropriately after a failed plugin update.
+	 *
+	 * @since 4.2.0
+	 * @since 4.6.0 More accurately named `updatePluginError`.
+	 *
+	 * @typedef {object} updatePluginError
+	 * @param {object}  response              Response from the server.
+	 * @param {string}  response.slug         Slug of the plugin to be updated.
+	 * @param {string}  response.plugin       Basename of the plugin to be updated.
+	 * @param {string=} response.pluginName   Optional. Name of the plugin to be updated.
+	 * @param {string}  response.errorCode    Error code for the error that occurred.
+	 * @param {string}  response.errorMessage The error that occurred.
+	 */
+	wp.updates.updatePluginError = function( response ) {
+		var $card, $message, errorMessage;
+
+		if ( ! wp.updates.isValidResponse( response, 'update' ) ) {
+			return;
+		}
+
+		if ( wp.updates.maybeHandleCredentialError( response, 'update-plugin' ) ) {
+			return;
+		}
+
+		errorMessage = wp.updates.l10n.updateFailed.replace( '%s', response.errorMessage );
+
+		if ( 'plugins' === pagenow || 'plugins-network' === pagenow ) {
+			if ( response.plugin ) {
+				$message = $( 'tr[data-plugin="' + response.plugin + '"]' ).find( '.update-message' );
+			} else {
+				$message = $( 'tr[data-slug="' + response.slug + '"]' ).find( '.update-message' );
+			}
+			$message.removeClass( 'updating-message notice-warning' ).addClass( 'notice-error' ).find( 'p' ).html( errorMessage );
+
+			if ( response.pluginName ) {
+				$message.find( 'p' )
+					.attr( 'aria-label', wp.updates.l10n.pluginUpdateFailedLabel.replace( '%s', response.pluginName ) );
+			} else {
+				$message.find( 'p' ).removeAttr( 'aria-label' );
+			}
+		} else if ( 'plugin-install' === pagenow || 'plugin-install-network' === pagenow ) {
+			$card = $( '.plugin-card-' + response.slug )
+				.addClass( 'plugin-card-update-failed' )
+				.append( wp.updates.adminNotice( {
+					className: 'update-message notice-error notice-alt is-dismissible',
+					message:   errorMessage
+				} ) );
+
+			$card.find( '.update-now' )
+				.text( wp.updates.l10n.updateFailedShort ).removeClass( 'updating-message' );
 
-		wp.ajax.post( 'update-plugin', data )
-			.done( wp.updates.updateSuccess )
-			.fail( wp.updates.updateError );
+			if ( response.pluginName ) {
+				$card.find( '.update-now' )
+					.attr( 'aria-label', wp.updates.l10n.pluginUpdateFailedLabel.replace( '%s', response.pluginName ) );
+			} else {
+				$card.find( '.update-now' ).removeAttr( 'aria-label' );
+			}
+
+			$card.on( 'click', '.notice.is-dismissible .notice-dismiss', function() {
+
+				// Use same delay as the total duration of the notice fadeTo + slideUp animation.
+				setTimeout( function() {
+					$card
+						.removeClass( 'plugin-card-update-failed' )
+						.find( '.column-name a' ).focus();
+
+					$card.find( '.update-now' )
+						.attr( 'aria-label', false )
+						.text( wp.updates.l10n.updateNow );
+				}, 200 );
+			} );
+		}
+
+		wp.a11y.speak( errorMessage, 'assertive' );
+
+		$document.trigger( 'wp-plugin-update-error', response );
+	};
+
+	/**
+	 * Sends an Ajax request to the server to install a plugin.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @param {object}                args         Arguments.
+	 * @param {string}                args.slug    Plugin identifier in the WordPress.org Plugin repository.
+	 * @param {installPluginSuccess=} args.success Optional. Success callback. Default: wp.updates.installPluginSuccess
+	 * @param {installPluginError=}   args.error   Optional. Error callback. Default: wp.updates.installPluginError
+	 * @return {$.promise} A jQuery promise that represents the request,
+	 *                     decorated with an abort() method.
+	 */
+	wp.updates.installPlugin = function( args ) {
+		var $card    = $( '.plugin-card-' + args.slug ),
+			$message = $card.find( '.install-now' );
+
+		args = _.extend( {
+			success: wp.updates.installPluginSuccess,
+			error: wp.updates.installPluginError
+		}, args );
+
+		if ( 'import' === pagenow ) {
+			$message = $( '[data-slug="' + args.slug + '"]' );
+		}
+
+		if ( $message.html() !== wp.updates.l10n.installing ) {
+			$message.data( 'originaltext', $message.html() );
+		}
+
+		$message
+			.addClass( 'updating-message' )
+			.attr( 'aria-label', wp.updates.l10n.pluginInstallingLabel.replace( '%s', $message.data( 'name' ) ) )
+			.text( wp.updates.l10n.installing );
+
+		wp.a11y.speak( wp.updates.l10n.installingMsg, 'polite' );
+
+		// Remove previous error messages, if any.
+		$card.removeClass( 'plugin-card-install-failed' ).find( '.notice.notice-error' ).remove();
+
+		$document.trigger( 'wp-plugin-installing', args );
+
+		return wp.updates.ajax( 'install-plugin', args );
+	};
+
+	/**
+	 * Updates the UI appropriately after a successful plugin install.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @typedef {object} installPluginSuccess
+	 * @param {object} response             Response from the server.
+	 * @param {string} response.slug        Slug of the installed plugin.
+	 * @param {string} response.pluginName  Name of the installed plugin.
+	 * @param {string} response.activateUrl URL to activate the just installed plugin.
+	 */
+	wp.updates.installPluginSuccess = function( response ) {
+		var $message = $( '.plugin-card-' + response.slug ).find( '.install-now' );
+
+		$message
+			.removeClass( 'updating-message' )
+			.addClass( 'updated-message installed' )
+			.attr( 'aria-label', wp.updates.l10n.pluginInstalledLabel.replace( '%s', response.pluginName ) )
+			.text( wp.updates.l10n.pluginInstalled );
+
+		if ( $message.hasClass( 'button-primary' ) ) {
+			$message.addClass( 'button-primary-disabled' );
+		} else {
+			$message.addClass( 'button-disabled' );
+		}
+
+		wp.a11y.speak( wp.updates.l10n.installedMsg, 'polite' );
+
+		$document.trigger( 'wp-plugin-install-success', response );
+
+		if ( response.activateUrl ) {
+			setTimeout( function() {
+
+				// Transform the 'Install' button into an 'Activate' button.
+				$message.removeClass( 'install-now installed button-primary-disabled button-secondary-disabled button-disabled updated-message' )
+					.addClass( 'activate-now' )
+					.attr( 'href', response.activateUrl )
+					.attr( 'aria-label', wp.updates.l10n.activatePluginLabel.replace( '%s', response.pluginName ) )
+					.text( response.activateLabel || wp.updates.l10n.activatePlugin );
+			}, 1000 );
+		}
+	};
+
+	/**
+	 * Updates the UI appropriately after a failed plugin install.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @typedef {object} installPluginError
+	 * @param {object}  response              Response from the server.
+	 * @param {string}  response.slug         Slug of the plugin to be installed.
+	 * @param {string=} response.pluginName   Optional. Name of the plugin to be installed.
+	 * @param {string}  response.errorCode    Error code for the error that occurred.
+	 * @param {string}  response.errorMessage The error that occurred.
+	 */
+	wp.updates.installPluginError = function( response ) {
+		var $card   = $( '.plugin-card-' + response.slug ),
+			$button = $card.find( '.install-now' ),
+			errorMessage;
+
+		if ( ! wp.updates.isValidResponse( response, 'install' ) ) {
+			return;
+		}
+
+		if ( wp.updates.maybeHandleCredentialError( response, 'install-plugin' ) ) {
+			return;
+		}
+
+		errorMessage = wp.updates.l10n.installFailed.replace( '%s', response.errorMessage );
+
+		$card
+			.addClass( 'plugin-card-update-failed' )
+			.append( '<div class="notice notice-error notice-alt is-dismissible"><p>' + errorMessage + '</p></div>' );
+
+		$card.on( 'click', '.notice.is-dismissible .notice-dismiss', function() {
+
+			// Use same delay as the total duration of the notice fadeTo + slideUp animation.
+			setTimeout( function() {
+				$card
+					.removeClass( 'plugin-card-update-failed' )
+					.find( '.column-name a' ).focus();
+			}, 200 );
+		} );
+
+		$button
+			.removeClass( 'updating-message' ).addClass( 'button-disabled' )
+			.attr( 'aria-label', wp.updates.l10n.pluginInstallFailedLabel.replace( '%s', $button.data( 'name' ) ) )
+			.text( wp.updates.l10n.installFailedShort );
+
+		wp.a11y.speak( errorMessage, 'assertive' );
+
+		$document.trigger( 'wp-plugin-install-error', response );
+	};
+
+	/**
+	 * Updates the UI appropriately after a successful importer install.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @typedef {object} installImporterSuccess
+	 * @param {object} response             Response from the server.
+	 * @param {string} response.slug        Slug of the installed plugin.
+	 * @param {string} response.pluginName  Name of the installed plugin.
+	 * @param {string} response.activateUrl URL to activate the just installed plugin.
+	 */
+	wp.updates.installImporterSuccess = function( response ) {
+		wp.updates.addAdminNotice( {
+			id:        'install-success',
+			className: 'notice-success is-dismissible',
+			message:   wp.updates.l10n.importerInstalledMsg.replace( '%s', response.activateUrl + '&from=import' )
+		} );
+
+		$( '[data-slug="' + response.slug + '"]' )
+			.removeClass( 'install-now updating-message' )
+			.addClass( 'activate-now' )
+			.attr({
+				'href': response.activateUrl + '&from=import',
+				'aria-label': wp.updates.l10n.activateImporterLabel.replace( '%s', response.pluginName )
+			})
+			.text( wp.updates.l10n.activateImporter );
+
+		wp.a11y.speak( wp.updates.l10n.installedMsg, 'polite' );
+
+		$document.trigger( 'wp-importer-install-success', response );
+	};
+
+	/**
+	 * Updates the UI appropriately after a failed importer install.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @typedef {object} installImporterError
+	 * @param {object}  response              Response from the server.
+	 * @param {string}  response.slug         Slug of the plugin to be installed.
+	 * @param {string=} response.pluginName   Optional. Name of the plugin to be installed.
+	 * @param {string}  response.errorCode    Error code for the error that occurred.
+	 * @param {string}  response.errorMessage The error that occurred.
+	 */
+	wp.updates.installImporterError = function( response ) {
+		var errorMessage = wp.updates.l10n.installFailed.replace( '%s', response.errorMessage ),
+			$installLink = $( '[data-slug="' + response.slug + '"]' ),
+			pluginName = $installLink.data( 'name' );
+
+		if ( ! wp.updates.isValidResponse( response, 'install' ) ) {
+			return;
+		}
+
+		if ( wp.updates.maybeHandleCredentialError( response, 'install-plugin' ) ) {
+			return;
+		}
+
+		wp.updates.addAdminNotice( {
+			id:        response.errorCode,
+			className: 'notice-error is-dismissible',
+			message:   errorMessage
+		} );
+
+		$installLink
+			.removeClass( 'updating-message' )
+			.text( wp.updates.l10n.installNow )
+			.attr( 'aria-label', wp.updates.l10n.installNowLabel.replace( '%s', pluginName ) );
+
+		wp.a11y.speak( errorMessage, 'assertive' );
+
+		$document.trigger( 'wp-importer-install-error', response );
+	};
+
+	/**
+	 * Sends an Ajax request to the server to delete a plugin.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @param {object}               args         Arguments.
+	 * @param {string}               args.plugin  Basename of the plugin to be deleted.
+	 * @param {string}               args.slug    Slug of the plugin to be deleted.
+	 * @param {deletePluginSuccess=} args.success Optional. Success callback. Default: wp.updates.deletePluginSuccess
+	 * @param {deletePluginError=}   args.error   Optional. Error callback. Default: wp.updates.deletePluginError
+	 * @return {$.promise} A jQuery promise that represents the request,
+	 *                     decorated with an abort() method.
+	 */
+	wp.updates.deletePlugin = function( args ) {
+		var $link = $( '[data-plugin="' + args.plugin + '"]' ).find( '.row-actions a.delete' );
+
+		args = _.extend( {
+			success: wp.updates.deletePluginSuccess,
+			error: wp.updates.deletePluginError
+		}, args );
+
+		if ( $link.html() !== wp.updates.l10n.deleting ) {
+			$link
+				.data( 'originaltext', $link.html() )
+				.text( wp.updates.l10n.deleting );
+		}
+
+		wp.a11y.speak( wp.updates.l10n.deleting, 'polite' );
+
+		$document.trigger( 'wp-plugin-deleting', args );
+
+		return wp.updates.ajax( 'delete-plugin', args );
 	};
 
 	/**
-	 * On a successful plugin update, update the UI with the result.
+	 * Updates the UI appropriately after a successful plugin deletion.
+	 *
+	 * @since 4.6.0
 	 *
-	 * @since 4.2.0
+	 * @typedef {object} deletePluginSuccess
+	 * @param {object} response            Response from the server.
+	 * @param {string} response.slug       Slug of the plugin that was deleted.
+	 * @param {string} response.plugin     Base name of the plugin that was deleted.
+	 * @param {string} response.pluginName Name of the plugin that was deleted.
+	 */
+	wp.updates.deletePluginSuccess = function( response ) {
+
+		// Removes the plugin and updates rows.
+		$( '[data-plugin="' + response.plugin + '"]' ).css( { backgroundColor: '#faafaa' } ).fadeOut( 350, function() {
+			var $form            = $( '#bulk-action-form' ),
+				$views           = $( '.subsubsub' ),
+				$pluginRow       = $( this ),
+				columnCount      = $form.find( 'thead th:not(.hidden), thead td' ).length,
+				pluginDeletedRow = wp.template( 'item-deleted-row' ),
+				/** @type {object} plugins Base names of plugins in their different states. */
+				plugins          = settings.plugins;
+
+			// Add a success message after deleting a plugin.
+			if ( ! $pluginRow.hasClass( 'plugin-update-tr' ) ) {
+				$pluginRow.after(
+					pluginDeletedRow( {
+						slug:    response.slug,
+						plugin:  response.plugin,
+						colspan: columnCount,
+						name:    response.pluginName
+					} )
+				);
+			}
+
+			$pluginRow.remove();
+
+			// Remove plugin from update count.
+			if ( -1 !== _.indexOf( plugins.upgrade, response.plugin ) ) {
+				plugins.upgrade = _.without( plugins.upgrade, response.plugin );
+				wp.updates.decrementCount( 'plugin' );
+			}
+
+			// Remove from views.
+			if ( -1 !== _.indexOf( plugins.inactive, response.plugin ) ) {
+				plugins.inactive = _.without( plugins.inactive, response.plugin );
+				if ( plugins.inactive.length ) {
+					$views.find( '.inactive .count' ).text( '(' + plugins.inactive.length + ')' );
+				} else {
+					$views.find( '.inactive' ).remove();
+				}
+			}
+
+			if ( -1 !== _.indexOf( plugins.active, response.plugin ) ) {
+				plugins.active = _.without( plugins.active, response.plugin );
+				if ( plugins.active.length ) {
+					$views.find( '.active .count' ).text( '(' + plugins.active.length + ')' );
+				} else {
+					$views.find( '.active' ).remove();
+				}
+			}
+
+			if ( -1 !== _.indexOf( plugins.recently_activated, response.plugin ) ) {
+				plugins.recently_activated = _.without( plugins.recently_activated, response.plugin );
+				if ( plugins.recently_activated.length ) {
+					$views.find( '.recently_activated .count' ).text( '(' + plugins.recently_activated.length + ')' );
+				} else {
+					$views.find( '.recently_activated' ).remove();
+				}
+			}
+
+			plugins.all = _.without( plugins.all, response.plugin );
+
+			if ( plugins.all.length ) {
+				$views.find( '.all .count' ).text( '(' + plugins.all.length + ')' );
+			} else {
+				$form.find( '.tablenav' ).css( { visibility: 'hidden' } );
+				$views.find( '.all' ).remove();
+
+				if ( ! $form.find( 'tr.no-items' ).length ) {
+					$form.find( '#the-list' ).append( '<tr class="no-items"><td class="colspanchange" colspan="' + columnCount + '">' + wp.updates.l10n.noPlugins + '</td></tr>' );
+				}
+			}
+		} );
+
+		wp.a11y.speak( wp.updates.l10n.pluginDeleted, 'polite' );
+
+		$document.trigger( 'wp-plugin-delete-success', response );
+	};
+
+	/**
+	 * Updates the UI appropriately after a failed plugin deletion.
 	 *
-	 * @param {object} response
+	 * @since 4.6.0
+	 *
+	 * @typedef {object} deletePluginError
+	 * @param {object}  response              Response from the server.
+	 * @param {string}  response.slug         Slug of the plugin to be deleted.
+	 * @param {string}  response.plugin       Base name of the plugin to be deleted
+	 * @param {string=} response.pluginName   Optional. Name of the plugin to be deleted.
+	 * @param {string}  response.errorCode    Error code for the error that occurred.
+	 * @param {string}  response.errorMessage The error that occurred.
 	 */
-	wp.updates.updateSuccess = function( response ) {
-		var $updateMessage, name, $pluginRow, newText;
-		if ( 'plugins' === pagenow || 'plugins-network' === pagenow ) {
-			$pluginRow = $( '[data-slug="' + response.slug + '"]' ).first();
-			$updateMessage = $pluginRow.next().find( '.update-message' );
-			$pluginRow.addClass( 'updated' ).removeClass( 'update' );
+	wp.updates.deletePluginError = function( response ) {
+		var $plugin, $pluginUpdateRow,
+			pluginUpdateRow  = wp.template( 'item-update-row' ),
+			noticeContent    = wp.updates.adminNotice( {
+				className: 'update-message notice-error notice-alt',
+				message:   response.errorMessage
+			} );
+
+		if ( response.plugin ) {
+			$plugin          = $( 'tr.inactive[data-plugin="' + response.plugin + '"]' );
+			$pluginUpdateRow = $plugin.siblings( '[data-plugin="' + response.plugin + '"]' );
+		} else {
+			$plugin          = $( 'tr.inactive[data-slug="' + response.slug + '"]' );
+			$pluginUpdateRow = $plugin.siblings( '[data-slug="' + response.slug + '"]' );
+		}
+
+		if ( ! wp.updates.isValidResponse( response, 'delete' ) ) {
+			return;
+		}
+
+		if ( wp.updates.maybeHandleCredentialError( response, 'delete-plugin' ) ) {
+			return;
+		}
+
+		// Add a plugin update row if it doesn't exist yet.
+		if ( ! $pluginUpdateRow.length ) {
+			$plugin.addClass( 'update' ).after(
+				pluginUpdateRow( {
+					slug:    response.slug,
+					plugin:  response.plugin || response.slug,
+					colspan: $( '#bulk-action-form' ).find( 'thead th:not(.hidden), thead td' ).length,
+					content: noticeContent
+				} )
+			);
+		} else {
+
+			// Remove previous error messages, if any.
+			$pluginUpdateRow.find( '.notice-error' ).remove();
+
+			$pluginUpdateRow.find( '.plugin-update' ).append( noticeContent );
+		}
+
+		$document.trigger( 'wp-plugin-delete-error', response );
+	};
+
+	/**
+	 * Sends an Ajax request to the server to update a theme.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @param {object}              args         Arguments.
+	 * @param {string}              args.slug    Theme stylesheet.
+	 * @param {updateThemeSuccess=} args.success Optional. Success callback. Default: wp.updates.updateThemeSuccess
+	 * @param {updateThemeError=}   args.error   Optional. Error callback. Default: wp.updates.updateThemeError
+	 * @return {$.promise} A jQuery promise that represents the request,
+	 *                     decorated with an abort() method.
+	 */
+	wp.updates.updateTheme = function( args ) {
+		var $notice;
+
+		args = _.extend( {
+			success: wp.updates.updateThemeSuccess,
+			error: wp.updates.updateThemeError
+		}, args );
+
+		if ( 'themes-network' === pagenow ) {
+			$notice = $( '[data-slug="' + args.slug + '"]' ).find( '.update-message' ).removeClass( 'notice-error' ).addClass( 'updating-message notice-warning' ).find( 'p' );
+
+		} else if ( 'customize' === pagenow ) {
+
+			// Update the theme details UI.
+			$notice = $( '[data-slug="' + args.slug + '"].notice' ).removeClass( 'notice-large' );
+
+			$notice.find( 'h3' ).remove();
+
+			// Add the top-level UI, and update both.
+			$notice = $notice.add( $( '#customize-control-installed_theme_' + args.slug ).find( '.update-message' ) );
+			$notice = $notice.addClass( 'updating-message' ).find( 'p' );
+
+		} else {
+			$notice = $( '#update-theme' ).closest( '.notice' ).removeClass( 'notice-large' );
+
+			$notice.find( 'h3' ).remove();
+
+			$notice = $notice.add( $( '[data-slug="' + args.slug + '"]' ).find( '.update-message' ) );
+			$notice = $notice.addClass( 'updating-message' ).find( 'p' );
+		}
+
+		if ( $notice.html() !== wp.updates.l10n.updating ) {
+			$notice.data( 'originaltext', $notice.html() );
+		}
+
+		wp.a11y.speak( wp.updates.l10n.updatingMsg, 'polite' );
+		$notice.text( wp.updates.l10n.updating );
+
+		$document.trigger( 'wp-theme-updating', args );
+
+		return wp.updates.ajax( 'update-theme', args );
+	};
+
+	/**
+	 * Updates the UI appropriately after a successful theme update.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @typedef {object} updateThemeSuccess
+	 * @param {object} response
+	 * @param {string} response.slug       Slug of the theme to be updated.
+	 * @param {object} response.theme      Updated theme.
+	 * @param {string} response.oldVersion Old version of the theme.
+	 * @param {string} response.newVersion New version of the theme.
+	 */
+	wp.updates.updateThemeSuccess = function( response ) {
+		var isModalOpen    = $( 'body.modal-open' ).length,
+			$theme         = $( '[data-slug="' + response.slug + '"]' ),
+			updatedMessage = {
+				className: 'updated-message notice-success notice-alt',
+				message:   wp.updates.l10n.themeUpdated
+			},
+			$notice, newText;
+
+		if ( 'customize' === pagenow ) {
+			$theme = $( '.updating-message' ).siblings( '.theme-name' );
+
+			if ( $theme.length ) {
+
+				// Update the version number in the row.
+				newText = $theme.html().replace( response.oldVersion, response.newVersion );
+				$theme.html( newText );
+			}
+
+			$notice = $( '.theme-info .notice' ).add( wp.customize.control( 'installed_theme_' + response.slug ).container.find( '.theme' ).find( '.update-message' ) );
+		} else if ( 'themes-network' === pagenow ) {
+			$notice = $theme.find( '.update-message' );
 
 			// Update the version number in the row.
-			newText = $pluginRow.find('.plugin-version-author-uri').html().replace( response.oldVersion, response.newVersion );
-			$pluginRow.find('.plugin-version-author-uri').html( newText );
+			newText = $theme.find( '.theme-version-author-uri' ).html().replace( response.oldVersion, response.newVersion );
+			$theme.find( '.theme-version-author-uri' ).html( newText );
+		} else {
+			$notice = $( '.theme-info .notice' ).add( $theme.find( '.update-message' ) );
+
+			// Focus on Customize button after updating.
+			if ( isModalOpen ) {
+				$( '.load-customize:visible' ).focus();
+			} else {
+				$theme.find( '.load-customize' ).focus();
+			}
+		}
+
+		wp.updates.addAdminNotice( _.extend( { selector: $notice }, updatedMessage ) );
+		wp.a11y.speak( wp.updates.l10n.updatedMsg, 'polite' );
+
+		wp.updates.decrementCount( 'theme' );
+
+		$document.trigger( 'wp-theme-update-success', response );
+
+		// Show updated message after modal re-rendered.
+		if ( isModalOpen && 'customize' !== pagenow ) {
+			$( '.theme-info .theme-author' ).after( wp.updates.adminNotice( updatedMessage ) );
+		}
+	};
+
+	/**
+	 * Updates the UI appropriately after a failed theme update.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @typedef {object} updateThemeError
+	 * @param {object} response              Response from the server.
+	 * @param {string} response.slug         Slug of the theme to be updated.
+	 * @param {string} response.errorCode    Error code for the error that occurred.
+	 * @param {string} response.errorMessage The error that occurred.
+	 */
+	wp.updates.updateThemeError = function( response ) {
+		var $theme       = $( '[data-slug="' + response.slug + '"]' ),
+			errorMessage = wp.updates.l10n.updateFailed.replace( '%s', response.errorMessage ),
+			$notice;
+
+		if ( ! wp.updates.isValidResponse( response, 'update' ) ) {
+			return;
+		}
+
+		if ( wp.updates.maybeHandleCredentialError( response, 'update-theme' ) ) {
+			return;
+		}
+
+		if ( 'customize' === pagenow ) {
+			$theme = wp.customize.control( 'installed_theme_' + response.slug ).container.find( '.theme' );
+		}
+
+		if ( 'themes-network' === pagenow ) {
+			$notice = $theme.find( '.update-message ' );
+		} else {
+			$notice = $( '.theme-info .notice' ).add( $theme.find( '.notice' ) );
+
+			$( 'body.modal-open' ).length ? $( '.load-customize:visible' ).focus() : $theme.find( '.load-customize' ).focus();
+		}
+
+		wp.updates.addAdminNotice( {
+			selector:  $notice,
+			className: 'update-message notice-error notice-alt is-dismissible',
+			message:   errorMessage
+		} );
+
+		wp.a11y.speak( errorMessage, 'polite' );
+
+		$document.trigger( 'wp-theme-update-error', response );
+	};
+
+	/**
+	 * Sends an Ajax request to the server to install a theme.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @param {object}               args
+	 * @param {string}               args.slug    Theme stylesheet.
+	 * @param {installThemeSuccess=} args.success Optional. Success callback. Default: wp.updates.installThemeSuccess
+	 * @param {installThemeError=}   args.error   Optional. Error callback. Default: wp.updates.installThemeError
+	 * @return {$.promise} A jQuery promise that represents the request,
+	 *                     decorated with an abort() method.
+	 */
+	wp.updates.installTheme = function( args ) {
+		var $message = $( '.theme-install[data-slug="' + args.slug + '"]' );
+
+		args = _.extend( {
+			success: wp.updates.installThemeSuccess,
+			error: wp.updates.installThemeError
+		}, args );
+
+		$message.addClass( 'updating-message' );
+		$message.parents( '.theme' ).addClass( 'focus' );
+		if ( $message.html() !== wp.updates.l10n.installing ) {
+			$message.data( 'originaltext', $message.html() );
+		}
+
+		$message
+			.text( wp.updates.l10n.installing )
+			.attr( 'aria-label', wp.updates.l10n.themeInstallingLabel.replace( '%s', $message.data( 'name' ) ) );
+		wp.a11y.speak( wp.updates.l10n.installingMsg, 'polite' );
 
-			// Add updated class to update message parent tr
-			$pluginRow.next().addClass( 'updated' );
-		} else if ( 'plugin-install' === pagenow ) {
-			$updateMessage = $( '.plugin-card-' + response.slug ).find( '.update-now' );
-			$updateMessage.addClass( 'button-disabled' );
-			name = $updateMessage.data( 'name' );
-			$updateMessage.attr( 'aria-label', wp.updates.l10n.updatedLabel.replace( '%s', name ) );
+		// Remove previous error messages, if any.
+		$( '.install-theme-info, [data-slug="' + args.slug + '"]' ).removeClass( 'theme-install-failed' ).find( '.notice.notice-error' ).remove();
+
+		$document.trigger( 'wp-theme-installing', args );
+
+		return wp.updates.ajax( 'install-theme', args );
+	};
+
+	/**
+	 * Updates the UI appropriately after a successful theme install.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @typedef {object} installThemeSuccess
+	 * @param {object} response              Response from the server.
+	 * @param {string} response.slug         Slug of the theme to be installed.
+	 * @param {string} response.customizeUrl URL to the Customizer for the just installed theme.
+	 * @param {string} response.activateUrl  URL to activate the just installed theme.
+	 */
+	wp.updates.installThemeSuccess = function( response ) {
+		var $card = $( '.wp-full-overlay-header, [data-slug=' + response.slug + ']' ),
+			$message;
+
+		$document.trigger( 'wp-theme-install-success', response );
+
+		$message = $card.find( '.button-primary' )
+			.removeClass( 'updating-message' )
+			.addClass( 'updated-message disabled' )
+			.attr( 'aria-label', wp.updates.l10n.themeInstalledLabel.replace( '%s', response.themeName ) )
+			.text( wp.updates.l10n.themeInstalled );
+
+		wp.a11y.speak( wp.updates.l10n.installedMsg, 'polite' );
+
+		setTimeout( function() {
+
+			if ( response.activateUrl ) {
+
+				// Transform the 'Install' button into an 'Activate' button.
+				$message
+					.attr( 'href', response.activateUrl )
+					.removeClass( 'theme-install updated-message disabled' )
+					.addClass( 'activate' )
+					.attr( 'aria-label', wp.updates.l10n.activateThemeLabel.replace( '%s', response.themeName ) )
+					.text( wp.updates.l10n.activateTheme );
+			}
+
+			if ( response.customizeUrl ) {
+
+				// Transform the 'Preview' button into a 'Live Preview' button.
+				$message.siblings( '.preview' ).replaceWith( function () {
+					return $( '<a>' )
+						.attr( 'href', response.customizeUrl )
+						.addClass( 'button load-customize' )
+						.text( wp.updates.l10n.livePreview );
+				} );
+			}
+		}, 1000 );
+	};
+
+	/**
+	 * Updates the UI appropriately after a failed theme install.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @typedef {object} installThemeError
+	 * @param {object} response              Response from the server.
+	 * @param {string} response.slug         Slug of the theme to be installed.
+	 * @param {string} response.errorCode    Error code for the error that occurred.
+	 * @param {string} response.errorMessage The error that occurred.
+	 */
+	wp.updates.installThemeError = function( response ) {
+		var $card, $button,
+			errorMessage = wp.updates.l10n.installFailed.replace( '%s', response.errorMessage ),
+			$message     = wp.updates.adminNotice( {
+				className: 'update-message notice-error notice-alt',
+				message:   errorMessage
+			} );
+
+		if ( ! wp.updates.isValidResponse( response, 'install' ) ) {
+			return;
+		}
+
+		if ( wp.updates.maybeHandleCredentialError( response, 'install-theme' ) ) {
+			return;
+		}
+
+		if ( 'customize' === pagenow ) {
+			if ( $document.find( 'body' ).hasClass( 'modal-open' ) ) {
+				$button = $( '.theme-install[data-slug="' + response.slug + '"]' );
+				$card   = $( '.theme-overlay .theme-info' ).prepend( $message );
+			} else {
+				$button = $( '.theme-install[data-slug="' + response.slug + '"]' );
+				$card   = $button.closest( '.theme' ).addClass( 'theme-install-failed' ).append( $message );
+			}
+			wp.customize.notifications.remove( 'theme_installing' );
+		} else {
+			if ( $document.find( 'body' ).hasClass( 'full-overlay-active' ) ) {
+				$button = $( '.theme-install[data-slug="' + response.slug + '"]' );
+				$card   = $( '.install-theme-info' ).prepend( $message );
+			} else {
+				$card   = $( '[data-slug="' + response.slug + '"]' ).removeClass( 'focus' ).addClass( 'theme-install-failed' ).append( $message );
+				$button = $card.find( '.theme-install' );
+			}
 		}
 
-		$updateMessage.removeClass( 'updating-message' ).addClass( 'updated-message' );
-		$updateMessage.text( wp.updates.l10n.updated );
-		wp.a11y.speak( wp.updates.l10n.updatedMsg );
+		$button
+			.removeClass( 'updating-message' )
+			.attr( 'aria-label', wp.updates.l10n.themeInstallFailedLabel.replace( '%s', $button.data( 'name' ) ) )
+			.text( wp.updates.l10n.installFailedShort );
+
+		wp.a11y.speak( errorMessage, 'assertive' );
+
+		$document.trigger( 'wp-theme-install-error', response );
+	};
+
+	/**
+	 * Sends an Ajax request to the server to delete a theme.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @param {object}              args
+	 * @param {string}              args.slug    Theme stylesheet.
+	 * @param {deleteThemeSuccess=} args.success Optional. Success callback. Default: wp.updates.deleteThemeSuccess
+	 * @param {deleteThemeError=}   args.error   Optional. Error callback. Default: wp.updates.deleteThemeError
+	 * @return {$.promise} A jQuery promise that represents the request,
+	 *                     decorated with an abort() method.
+	 */
+	wp.updates.deleteTheme = function( args ) {
+		var $button;
 
-		wp.updates.decrementCount( 'plugin' );
+		if ( 'themes' === pagenow ) {
+			$button = $( '.theme-actions .delete-theme' );
+		} else if ( 'themes-network' === pagenow ) {
+			$button = $( '[data-slug="' + args.slug + '"]' ).find( '.row-actions a.delete' );
+		}
+
+		args = _.extend( {
+			success: wp.updates.deleteThemeSuccess,
+			error: wp.updates.deleteThemeError
+		}, args );
 
-		wp.updates.updateDoneSuccessfully = true;
+		if ( $button && $button.html() !== wp.updates.l10n.deleting ) {
+			$button
+				.data( 'originaltext', $button.html() )
+				.text( wp.updates.l10n.deleting );
+		}
+
+		wp.a11y.speak( wp.updates.l10n.deleting, 'polite' );
+
+		// Remove previous error messages, if any.
+		$( '.theme-info .update-message' ).remove();
+
+		$document.trigger( 'wp-theme-deleting', args );
+
+		return wp.updates.ajax( 'delete-theme', args );
+	};
 
-		/*
-		 * The lock can be released since the update was successful,
-		 * and any other updates can commence.
-		 */
-		wp.updates.updateLock = false;
+	/**
+	 * Updates the UI appropriately after a successful theme deletion.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @typedef {object} deleteThemeSuccess
+	 * @param {object} response      Response from the server.
+	 * @param {string} response.slug Slug of the theme that was deleted.
+	 */
+	wp.updates.deleteThemeSuccess = function( response ) {
+		var $themeRows = $( '[data-slug="' + response.slug + '"]' );
+
+		if ( 'themes-network' === pagenow ) {
+
+			// Removes the theme and updates rows.
+			$themeRows.css( { backgroundColor: '#faafaa' } ).fadeOut( 350, function() {
+				var $views     = $( '.subsubsub' ),
+					$themeRow  = $( this ),
+					totals     = settings.themes,
+					deletedRow = wp.template( 'item-deleted-row' );
 
-		$(document).trigger( 'wp-plugin-update-success', response );
+				if ( ! $themeRow.hasClass( 'plugin-update-tr' ) ) {
+					$themeRow.after(
+						deletedRow( {
+							slug:    response.slug,
+							colspan: $( '#bulk-action-form' ).find( 'thead th:not(.hidden), thead td' ).length,
+							name:    $themeRow.find( '.theme-title strong' ).text()
+						} )
+					);
+				}
+
+				$themeRow.remove();
+
+				// Remove theme from update count.
+				if ( $themeRow.hasClass( 'update' ) ) {
+					totals.upgrade--;
+					wp.updates.decrementCount( 'theme' );
+				}
 
-		wp.updates.queueChecker();
+				// Remove from views.
+				if ( $themeRow.hasClass( 'inactive' ) ) {
+					totals.disabled--;
+					if ( totals.disabled ) {
+						$views.find( '.disabled .count' ).text( '(' + totals.disabled + ')' );
+					} else {
+						$views.find( '.disabled' ).remove();
+					}
+				}
+
+				// There is always at least one theme available.
+				$views.find( '.all .count' ).text( '(' + --totals.all + ')' );
+			} );
+		}
+
+		wp.a11y.speak( wp.updates.l10n.themeDeleted, 'polite' );
+
+		$document.trigger( 'wp-theme-delete-success', response );
 	};
 
+	/**
+	 * Updates the UI appropriately after a failed theme deletion.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @typedef {object} deleteThemeError
+	 * @param {object} response              Response from the server.
+	 * @param {string} response.slug         Slug of the theme to be deleted.
+	 * @param {string} response.errorCode    Error code for the error that occurred.
+	 * @param {string} response.errorMessage The error that occurred.
+	 */
+	wp.updates.deleteThemeError = function( response ) {
+		var $themeRow    = $( 'tr.inactive[data-slug="' + response.slug + '"]' ),
+			$button      = $( '.theme-actions .delete-theme' ),
+			updateRow    = wp.template( 'item-update-row' ),
+			$updateRow   = $themeRow.siblings( '#' + response.slug + '-update' ),
+			errorMessage = wp.updates.l10n.deleteFailed.replace( '%s', response.errorMessage ),
+			$message     = wp.updates.adminNotice( {
+				className: 'update-message notice-error notice-alt',
+				message:   errorMessage
+			} );
+
+		if ( wp.updates.maybeHandleCredentialError( response, 'delete-theme' ) ) {
+			return;
+		}
+
+		if ( 'themes-network' === pagenow ) {
+			if ( ! $updateRow.length ) {
+				$themeRow.addClass( 'update' ).after(
+					updateRow( {
+						slug: response.slug,
+						colspan: $( '#bulk-action-form' ).find( 'thead th:not(.hidden), thead td' ).length,
+						content: $message
+					} )
+				);
+			} else {
+				// Remove previous error messages, if any.
+				$updateRow.find( '.notice-error' ).remove();
+				$updateRow.find( '.plugin-update' ).append( $message );
+			}
+		} else {
+			$( '.theme-info .theme-description' ).before( $message );
+		}
+
+		$button.html( $button.data( 'originaltext' ) );
+
+		wp.a11y.speak( errorMessage, 'assertive' );
+
+		$document.trigger( 'wp-theme-delete-error', response );
+	};
 
 	/**
-	 * On a plugin update error, update the UI appropriately.
+	 * Adds the appropriate callback based on the type of action and the current page.
+	 *
+	 * @since 4.6.0
+	 * @private
+	 *
+	 * @param {object} data   AJAX payload.
+	 * @param {string} action The type of request to perform.
+	 * @return {object} The AJAX payload with the appropriate callbacks.
+	 */
+	wp.updates._addCallbacks = function( data, action ) {
+		if ( 'import' === pagenow && 'install-plugin' === action ) {
+			data.success = wp.updates.installImporterSuccess;
+			data.error   = wp.updates.installImporterError;
+		}
+
+		return data;
+	};
+
+	/**
+	 * Pulls available jobs from the queue and runs them.
+	 *
+	 * @since 4.2.0
+	 * @since 4.6.0 Can handle multiple job types.
+	 */
+	wp.updates.queueChecker = function() {
+		var job;
+
+		if ( wp.updates.ajaxLocked || ! wp.updates.queue.length ) {
+			return;
+		}
+
+		job = wp.updates.queue.shift();
+
+		// Handle a queue job.
+		switch ( job.action ) {
+			case 'install-plugin':
+				wp.updates.installPlugin( job.data );
+				break;
+
+			case 'update-plugin':
+				wp.updates.updatePlugin( job.data );
+				break;
+
+			case 'delete-plugin':
+				wp.updates.deletePlugin( job.data );
+				break;
+
+			case 'install-theme':
+				wp.updates.installTheme( job.data );
+				break;
+
+			case 'update-theme':
+				wp.updates.updateTheme( job.data );
+				break;
+
+			case 'delete-theme':
+				wp.updates.deleteTheme( job.data );
+				break;
+
+			default:
+				break;
+		}
+	};
+
+	/**
+	 * Requests the users filesystem credentials if they aren't already known.
 	 *
 	 * @since 4.2.0
 	 *
-	 * @param {object} response
+	 * @param {Event=} event Optional. Event interface.
 	 */
-	wp.updates.updateError = function( response ) {
-		var $message, name;
-		wp.updates.updateDoneSuccessfully = false;
-		if ( response.errorCode && response.errorCode == 'unable_to_connect_to_filesystem' ) {
-			wp.updates.credentialError( response, 'update-plugin' );
-			return;
-		}
-		if ( 'plugins' === pagenow || 'plugins-network' === pagenow ) {
-			$message = $( '[data-slug="' + response.slug + '"]' ).next().find( '.update-message' );
-		} else if ( 'plugin-install' === pagenow ) {
-			$message = $( '.plugin-card-' + response.slug ).find( '.update-now' );
+	wp.updates.requestFilesystemCredentials = function( event ) {
+		if ( false === wp.updates.filesystemCredentials.available ) {
+			/*
+			 * After exiting the credentials request modal,
+			 * return the focus to the element triggering the request.
+			 */
+			if ( event && ! wp.updates.$elToReturnFocusToFromCredentialsModal ) {
+				wp.updates.$elToReturnFocusToFromCredentialsModal = $( event.target );
+			}
 
-			name = $message.data( 'name' );
-			$message.attr( 'aria-label', wp.updates.l10n.updateFailedLabel.replace( '%s', name ) );
+			wp.updates.ajaxLocked = true;
+			wp.updates.requestForCredentialsModalOpen();
 		}
-		$message.removeClass( 'updating-message' );
-		$message.text( wp.updates.l10n.updateFailed );
-		wp.a11y.speak( wp.updates.l10n.updateFailed );
-
-		$(document).trigger( 'wp-plugin-update-error', response );
-	};
-
-	/**
-	 * Show an error message in the request for credentials form.
-	 *
-	 * @param {string} message
-	 * @since 4.2.0
-	 */
-	wp.updates.showErrorInCredentialsForm = function( message ) {
-		var $modal = $( '.notification-dialog' );
-
-		// Remove any existing error.
-		$modal.find( '.error' ).remove();
-
-		$modal.find( 'h3' ).after( '<div class="error">' + message + '</div>' );
 	};
 
 	/**
-	 * Events that need to happen when there is a credential error
+	 * Requests the users filesystem credentials if needed and there is no lock.
 	 *
-	 * @since 4.2.0
-	 */
-	wp.updates.credentialError = function( response, type ) {
-		wp.updates.updateQueue.push( {
-			'type': type,
-			'data': {
-				// Not cool that we're depending on response for this data.
-				// This would feel more whole in a view all tied together.
-				plugin: response.plugin,
-				slug: response.slug
-			}
-		} );
-		wp.updates.showErrorInCredentialsForm( response.error );
-		wp.updates.requestFilesystemCredentials();
-	};
-
-	/**
-	 * If an update job has been placed in the queue, queueChecker pulls it out and runs it.
+	 * @since 4.6.0
 	 *
-	 * @since 4.2.0
+	 * @param {Event=} event Optional. Event interface.
 	 */
-	wp.updates.queueChecker = function() {
-		if ( wp.updates.updateLock || wp.updates.updateQueue.length <= 0 ) {
-			return;
-		}
-
-		var job = wp.updates.updateQueue.shift();
-
-		wp.updates.updatePlugin( job.data.plugin, job.data.slug );
-	};
-
-
-	/**
-	 * Request the users filesystem credentials if we don't have them already.
-	 *
-	 * @since 4.2.0
-	 */
-	wp.updates.requestFilesystemCredentials = function( event ) {
-		if ( wp.updates.updateDoneSuccessfully === false ) {
-			/*
-			 * For the plugin install screen, return the focus to the install button
-			 * after exiting the credentials request modal.
-			 */
-			if ( 'plugin-install' === pagenow && event ) {
-				wp.updates.$elToReturnFocusToFromCredentialsModal = $( event.target );
-			}
-
-			wp.updates.updateLock = true;
-
-			wp.updates.requestForCredentialsModalOpen();
+	wp.updates.maybeRequestFilesystemCredentials = function( event ) {
+		if ( wp.updates.shouldRequestFilesystemCredentials && ! wp.updates.ajaxLocked ) {
+			wp.updates.requestFilesystemCredentials( event );
 		}
 	};
 
 	/**
 	 * Keydown handler for the request for credentials modal.
 	 *
-	 * Close the modal when the escape key is pressed.
-	 * Constrain keyboard navigation to inside the modal.
+	 * Closes the modal when the escape key is pressed and
+	 * constrains keyboard navigation to inside the modal.
 	 *
 	 * @since 4.2.0
+	 *
+	 * @param {Event} event Event interface.
 	 */
 	wp.updates.keydown = function( event ) {
 		if ( 27 === event.keyCode ) {
 			wp.updates.requestForCredentialsModalCancel();
 		} else if ( 9 === event.keyCode ) {
-			// #upgrade button must always be the last focusable element in the dialog.
-			if ( event.target.id === 'upgrade' && ! event.shiftKey ) {
+
+			// #upgrade button must always be the last focus-able element in the dialog.
+			if ( 'upgrade' === event.target.id && ! event.shiftKey ) {
 				$( '#hostname' ).focus();
+
 				event.preventDefault();
-			} else if ( event.target.id === 'hostname' && event.shiftKey ) {
+			} else if ( 'hostname' === event.target.id && event.shiftKey ) {
 				$( '#upgrade' ).focus();
+
 				event.preventDefault();
 			}
 		}
 	};
 
 	/**
-	 * Open the request for credentials modal.
+	 * Opens the request for credentials modal.
 	 *
 	 * @since 4.2.0
 	 */
 	wp.updates.requestForCredentialsModalOpen = function() {
 		var $modal = $( '#request-filesystem-credentials-dialog' );
+
 		$( 'body' ).addClass( 'modal-open' );
 		$modal.show();
-
 		$modal.find( 'input:enabled:first' ).focus();
-		$modal.keydown( wp.updates.keydown );
+		$modal.on( 'keydown', wp.updates.keydown );
 	};
 
 	/**
-	 * Close the request for credentials modal.
+	 * Closes the request for credentials modal.
 	 *
 	 * @since 4.2.0
 	 */
 	wp.updates.requestForCredentialsModalClose = function() {
 		$( '#request-filesystem-credentials-dialog' ).hide();
 		$( 'body' ).removeClass( 'modal-open' );
-		wp.updates.$elToReturnFocusToFromCredentialsModal.focus();
+
+		if ( wp.updates.$elToReturnFocusToFromCredentialsModal ) {
+			wp.updates.$elToReturnFocusToFromCredentialsModal.focus();
+		}
 	};
 
 	/**
-	 * The steps that need to happen when the modal is canceled out
+	 * Takes care of the steps that need to happen when the modal is canceled out.
 	 *
 	 * @since 4.2.0
+	 * @since 4.6.0 Triggers an event for callbacks to listen to and add their actions.
 	 */
 	wp.updates.requestForCredentialsModalCancel = function() {
-		// no updateLock and no updateQueue means we already have cleared things up
-		var slug, $message;
 
-		if( wp.updates.updateLock === false && wp.updates.updateQueue.length === 0 ){
+		// Not ajaxLocked and no queue means we already have cleared things up.
+		if ( ! wp.updates.ajaxLocked && ! wp.updates.queue.length ) {
 			return;
 		}
 
-		slug = wp.updates.updateQueue[0].data.slug,
+		_.each( wp.updates.queue, function( job ) {
+			$document.trigger( 'credential-modal-cancel', job );
+		} );
 
-		// remove the lock, and clear the queue
-		wp.updates.updateLock = false;
-		wp.updates.updateQueue = [];
+		// Remove the lock, and clear the queue.
+		wp.updates.ajaxLocked = false;
+		wp.updates.queue = [];
 
 		wp.updates.requestForCredentialsModalClose();
-		if ( 'plugins' === pagenow || 'plugins-network' === pagenow ) {
-			$message = $( '[data-slug="' + slug + '"]' ).next().find( '.update-message' );
-		} else if ( 'plugin-install' === pagenow ) {
-			$message = $( '.plugin-card-' + slug ).find( '.update-now' );
+	};
+
+	/**
+	 * Displays an error message in the request for credentials form.
+	 *
+	 * @since 4.2.0
+	 *
+	 * @param {string} message Error message.
+	 */
+	wp.updates.showErrorInCredentialsForm = function( message ) {
+		var $filesystemForm = $( '#request-filesystem-credentials-form' );
+
+		// Remove any existing error.
+		$filesystemForm.find( '.notice' ).remove();
+		$filesystemForm.find( '#request-filesystem-credentials-title' ).after( '<div class="notice notice-alt notice-error"><p>' + message + '</p></div>' );
+	};
+
+	/**
+	 * Handles credential errors and runs events that need to happen in that case.
+	 *
+	 * @since 4.2.0
+	 *
+	 * @param {object} response Ajax response.
+	 * @param {string} action   The type of request to perform.
+	 */
+	wp.updates.credentialError = function( response, action ) {
+
+		// Restore callbacks.
+		response = wp.updates._addCallbacks( response, action );
+
+		wp.updates.queue.unshift( {
+			action: action,
+
+			/*
+			 * Not cool that we're depending on response for this data.
+			 * This would feel more whole in a view all tied together.
+			 */
+			data: response
+		} );
+
+		wp.updates.filesystemCredentials.available = false;
+		wp.updates.showErrorInCredentialsForm( response.errorMessage );
+		wp.updates.requestFilesystemCredentials();
+	};
+
+	/**
+	 * Handles credentials errors if it could not connect to the filesystem.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @typedef {object} maybeHandleCredentialError
+	 * @param {object} response              Response from the server.
+	 * @param {string} response.errorCode    Error code for the error that occurred.
+	 * @param {string} response.errorMessage The error that occurred.
+	 * @param {string} action                The type of request to perform.
+	 * @returns {boolean} Whether there is an error that needs to be handled or not.
+	 */
+	wp.updates.maybeHandleCredentialError = function( response, action ) {
+		if ( wp.updates.shouldRequestFilesystemCredentials && response.errorCode && 'unable_to_connect_to_filesystem' === response.errorCode ) {
+			wp.updates.credentialError( response, action );
+			return true;
 		}
 
-		$message.removeClass( 'updating-message' );
-		$message.html( $message.data( 'originaltext' ) );
-		wp.a11y.speak( wp.updates.l10n.updateCancel );
+		return false;
 	};
+
 	/**
-	 * Potentially add an AYS to a user attempting to leave the page
+	 * Validates an AJAX response to ensure it's a proper object.
+	 *
+	 * If the response deems to be invalid, an admin notice is being displayed.
+	 *
+	 * @param {(object|string)} response              Response from the server.
+	 * @param {function=}       response.always       Optional. Callback for when the Deferred is resolved or rejected.
+	 * @param {string=}         response.statusText   Optional. Status message corresponding to the status code.
+	 * @param {string=}         response.responseText Optional. Request response as text.
+	 * @param {string}          action                Type of action the response is referring to. Can be 'delete',
+	 *                                                'update' or 'install'.
+	 */
+	wp.updates.isValidResponse = function( response, action ) {
+		var error = wp.updates.l10n.unknownError,
+		    errorMessage;
+
+		// Make sure the response is a valid data object and not a Promise object.
+		if ( _.isObject( response ) && ! _.isFunction( response.always ) ) {
+			return true;
+		}
+
+		if ( _.isString( response ) && '-1' === response ) {
+			error = wp.updates.l10n.nonceError;
+		} else if ( _.isString( response ) ) {
+			error = response;
+		} else if ( 'undefined' !== typeof response.readyState && 0 === response.readyState ) {
+			error = wp.updates.l10n.connectionError;
+		} else if ( _.isString( response.responseText ) && '' !== response.responseText ) {
+			error = response.responseText;
+		} else if ( _.isString( response.statusText ) ) {
+			error = response.statusText;
+		}
+
+		switch ( action ) {
+			case 'update':
+				errorMessage = wp.updates.l10n.updateFailed;
+				break;
+
+			case 'install':
+				errorMessage = wp.updates.l10n.installFailed;
+				break;
+
+			case 'delete':
+				errorMessage = wp.updates.l10n.deleteFailed;
+				break;
+		}
+
+		// Messages are escaped, remove HTML tags to make them more readable.
+		error = error.replace( /<[\/a-z][^<>]*>/gi, '' );
+		errorMessage = errorMessage.replace( '%s', error );
+
+		// Add admin notice.
+		wp.updates.addAdminNotice( {
+			id:        'unknown_error',
+			className: 'notice-error is-dismissible',
+			message:   _.escape( errorMessage )
+		} );
+
+		// Remove the lock, and clear the queue.
+		wp.updates.ajaxLocked = false;
+		wp.updates.queue      = [];
+
+		// Change buttons of all running updates.
+		$( '.button.updating-message' )
+			.removeClass( 'updating-message' )
+			.removeAttr( 'aria-label' )
+			.prop( 'disabled', true )
+			.text( wp.updates.l10n.updateFailedShort );
+
+		$( '.updating-message:not(.button):not(.thickbox)' )
+			.removeClass( 'updating-message notice-warning' )
+			.addClass( 'notice-error' )
+			.find( 'p' )
+				.removeAttr( 'aria-label' )
+				.text( errorMessage );
+
+		wp.a11y.speak( errorMessage, 'assertive' );
+
+		return false;
+	};
+
+	/**
+	 * Potentially adds an AYS to a user attempting to leave the page.
 	 *
 	 * If an update is on-going and a user attempts to leave the page,
-	 * open an "Are you sure?" alert.
+	 * opens an "Are you sure?" alert.
 	 *
 	 * @since 4.2.0
 	 */
-
 	wp.updates.beforeunload = function() {
-		if ( wp.updates.updateLock ) {
+		if ( wp.updates.ajaxLocked ) {
 			return wp.updates.l10n.beforeunload;
 		}
 	};
 
+	$( function() {
+		var $pluginFilter        = $( '#plugin-filter' ),
+			$bulkActionForm      = $( '#bulk-action-form' ),
+			$filesystemForm      = $( '#request-filesystem-credentials-form' ),
+			$filesystemModal     = $( '#request-filesystem-credentials-dialog' ),
+			$pluginSearch        = $( '.plugins-php .wp-filter-search' ),
+			$pluginInstallSearch = $( '.plugin-install-php .wp-filter-search' );
 
-	$( document ).ready( function() {
+		settings = _.extend( settings, window._wpUpdatesItemCounts || {} );
+
+		if ( settings.totals ) {
+			wp.updates.refreshCount();
+		}
+
 		/*
-		 * Check whether a user needs to submit filesystem credentials based on whether
-		 * the form was output on the page server-side.
+		 * Whether a user needs to submit filesystem credentials.
+		 *
+		 * This is based on whether the form was output on the page server-side.
 		 *
 		 * @see {wp_print_request_filesystem_credentials_modal() in PHP}
 		 */
-		wp.updates.shouldRequestFilesystemCredentials = ( $( '#request-filesystem-credentials-dialog' ).length <= 0 ) ? false : true;
+		wp.updates.shouldRequestFilesystemCredentials = $filesystemModal.length > 0;
 
-		// File system credentials form submit noop-er / handler.
-		$( '#request-filesystem-credentials-dialog form' ).on( 'submit', function() {
+		/**
+		 * File system credentials form submit noop-er / handler.
+		 *
+		 * @since 4.2.0
+		 */
+		$filesystemModal.on( 'submit', 'form', function( event ) {
+			event.preventDefault();
+
 			// Persist the credentials input by the user for the duration of the page load.
-			wp.updates.filesystemCredentials.ftp.hostname = $('#hostname').val();
-			wp.updates.filesystemCredentials.ftp.username = $('#username').val();
-			wp.updates.filesystemCredentials.ftp.password = $('#password').val();
-			wp.updates.filesystemCredentials.ftp.connectionType = $('input[name="connection_type"]:checked').val();
-			wp.updates.filesystemCredentials.ssh.publicKey = $('#public_key').val();
-			wp.updates.filesystemCredentials.ssh.privateKey = $('#private_key').val();
-
-			wp.updates.requestForCredentialsModalClose();
+			wp.updates.filesystemCredentials.ftp.hostname       = $( '#hostname' ).val();
+			wp.updates.filesystemCredentials.ftp.username       = $( '#username' ).val();
+			wp.updates.filesystemCredentials.ftp.password       = $( '#password' ).val();
+			wp.updates.filesystemCredentials.ftp.connectionType = $( 'input[name="connection_type"]:checked' ).val();
+			wp.updates.filesystemCredentials.ssh.publicKey      = $( '#public_key' ).val();
+			wp.updates.filesystemCredentials.ssh.privateKey     = $( '#private_key' ).val();
+			wp.updates.filesystemCredentials.fsNonce            = $( '#_fs_nonce' ).val();
+			wp.updates.filesystemCredentials.available          = true;
 
 			// Unlock and invoke the queue.
-			wp.updates.updateLock = false;
+			wp.updates.ajaxLocked = false;
 			wp.updates.queueChecker();
 
-			return false;
-		});
+			wp.updates.requestForCredentialsModalClose();
+		} );
+
+		/**
+		 * Closes the request credentials modal when clicking the 'Cancel' button or outside of the modal.
+		 *
+		 * @since 4.2.0
+		 */
+		$filesystemModal.on( 'click', '[data-js-action="close"], .notification-dialog-background', wp.updates.requestForCredentialsModalCancel );
+
+		/**
+		 * Hide SSH fields when not selected.
+		 *
+		 * @since 4.2.0
+		 */
+		$filesystemForm.on( 'change', 'input[name="connection_type"]', function() {
+			$( '#ssh-keys' ).toggleClass( 'hidden', ( 'ssh' !== $( this ).val() ) );
+		} ).change();
 
-		// Close the request credentials modal when
-		$( '#request-filesystem-credentials-dialog [data-js-action="close"], .notification-dialog-background' ).on( 'click', function() {
-			wp.updates.requestForCredentialsModalCancel();
-		});
+		/**
+		 * Handles events after the credential modal was closed.
+		 *
+		 * @since 4.6.0
+		 *
+		 * @param {Event}  event Event interface.
+		 * @param {string} job   The install/update.delete request.
+		 */
+		$document.on( 'credential-modal-cancel', function( event, job ) {
+			var $updatingMessage = $( '.updating-message' ),
+				$message, originalText;
+
+			if ( 'import' === pagenow ) {
+				$updatingMessage.removeClass( 'updating-message' );
+			} else if ( 'plugins' === pagenow || 'plugins-network' === pagenow ) {
+				if ( 'update-plugin' === job.action ) {
+					$message = $( 'tr[data-plugin="' + job.data.plugin + '"]' ).find( '.update-message' );
+				} else if ( 'delete-plugin' === job.action ) {
+					$message = $( '[data-plugin="' + job.data.plugin + '"]' ).find( '.row-actions a.delete' );
+				}
+			} else if ( 'themes' === pagenow || 'themes-network' === pagenow ) {
+				if ( 'update-theme' === job.action ) {
+					$message = $( '[data-slug="' + job.data.slug + '"]' ).find( '.update-message' );
+				} else if ( 'delete-theme' === job.action && 'themes-network' === pagenow ) {
+					$message = $( '[data-slug="' + job.data.slug + '"]' ).find( '.row-actions a.delete' );
+				} else if ( 'delete-theme' === job.action && 'themes' === pagenow ) {
+					$message = $( '.theme-actions .delete-theme' );
+				}
+			} else {
+				$message = $updatingMessage;
+			}
+
+			if ( $message && $message.hasClass( 'updating-message' ) ) {
+				originalText = $message.data( 'originaltext' );
+
+				if ( 'undefined' === typeof originalText ) {
+					originalText = $( '<p>' ).html( $message.find( 'p' ).data( 'originaltext' ) );
+				}
 
-		// Click handler for plugin updates in List Table view.
-		$( '.plugin-update-tr' ).on( 'click', '.update-link', function( e ) {
-			e.preventDefault();
-			if ( wp.updates.shouldRequestFilesystemCredentials && ! wp.updates.updateLock ) {
-				wp.updates.requestFilesystemCredentials( e );
+				$message
+					.removeClass( 'updating-message' )
+					.html( originalText );
+
+				if ( 'plugin-install' === pagenow || 'plugin-install-network' === pagenow ) {
+					if ( 'update-plugin' === job.action ) {
+						$message.attr( 'aria-label', wp.updates.l10n.pluginUpdateNowLabel.replace( '%s', $message.data( 'name' ) ) );
+					} else if ( 'install-plugin' === job.action ) {
+						$message.attr( 'aria-label', wp.updates.l10n.pluginInstallNowLabel.replace( '%s', $message.data( 'name' ) ) );
+					}
+				}
+			}
+
+			wp.a11y.speak( wp.updates.l10n.updateCancel, 'polite' );
+		} );
+
+		/**
+		 * Click handler for plugin updates in List Table view.
+		 *
+		 * @since 4.2.0
+		 *
+		 * @param {Event} event Event interface.
+		 */
+		$bulkActionForm.on( 'click', '[data-plugin] .update-link', function( event ) {
+			var $message   = $( event.target ),
+				$pluginRow = $message.parents( 'tr' );
+
+			event.preventDefault();
+
+			if ( $message.hasClass( 'updating-message' ) || $message.hasClass( 'button-disabled' ) ) {
+				return;
 			}
-			var updateRow = $( e.target ).parents( '.plugin-update-tr' );
+
+			wp.updates.maybeRequestFilesystemCredentials( event );
+
 			// Return the user to the input box of the plugin's table row after closing the modal.
-			wp.updates.$elToReturnFocusToFromCredentialsModal = $( '#' + updateRow.data( 'slug' ) ).find( '.check-column input' );
-			wp.updates.updatePlugin( updateRow.data( 'plugin' ), updateRow.data( 'slug' ) );
+			wp.updates.$elToReturnFocusToFromCredentialsModal = $pluginRow.find( '.check-column input' );
+			wp.updates.updatePlugin( {
+				plugin: $pluginRow.data( 'plugin' ),
+				slug:   $pluginRow.data( 'slug' )
+			} );
+		} );
+
+		/**
+		 * Click handler for plugin updates in plugin install view.
+		 *
+		 * @since 4.2.0
+		 *
+		 * @param {Event} event Event interface.
+		 */
+		$pluginFilter.on( 'click', '.update-now', function( event ) {
+			var $button = $( event.target );
+			event.preventDefault();
+
+			if ( $button.hasClass( 'updating-message' ) || $button.hasClass( 'button-disabled' ) ) {
+				return;
+			}
+
+			wp.updates.maybeRequestFilesystemCredentials( event );
+
+			wp.updates.updatePlugin( {
+				plugin: $button.data( 'plugin' ),
+				slug:   $button.data( 'slug' )
+			} );
 		} );
 
-		$( '.plugin-card' ).on( 'click', '.update-now', function( e ) {
-			e.preventDefault();
-			var $button = $( e.target );
+		/**
+		 * Click handler for plugin installs in plugin install view.
+		 *
+		 * @since 4.6.0
+		 *
+		 * @param {Event} event Event interface.
+		 */
+		$pluginFilter.on( 'click', '.install-now', function( event ) {
+			var $button = $( event.target );
+			event.preventDefault();
+
+			if ( $button.hasClass( 'updating-message' ) || $button.hasClass( 'button-disabled' ) ) {
+				return;
+			}
+
+			if ( wp.updates.shouldRequestFilesystemCredentials && ! wp.updates.ajaxLocked ) {
+				wp.updates.requestFilesystemCredentials( event );
+
+				$document.on( 'credential-modal-cancel', function() {
+					var $message = $( '.install-now.updating-message' );
+
+					$message
+						.removeClass( 'updating-message' )
+						.text( wp.updates.l10n.installNow );
+
+					wp.a11y.speak( wp.updates.l10n.updateCancel, 'polite' );
+				} );
+			}
 
-			if ( wp.updates.shouldRequestFilesystemCredentials && ! wp.updates.updateLock ) {
-				wp.updates.requestFilesystemCredentials( e );
+			wp.updates.installPlugin( {
+				slug: $button.data( 'slug' )
+			} );
+		} );
+
+		/**
+		 * Click handler for importer plugins installs in the Import screen.
+		 *
+		 * @since 4.6.0
+		 *
+		 * @param {Event} event Event interface.
+		 */
+		$document.on( 'click', '.importer-item .install-now', function( event ) {
+			var $button = $( event.target ),
+				pluginName = $( this ).data( 'name' );
+
+			event.preventDefault();
+
+			if ( $button.hasClass( 'updating-message' ) ) {
+				return;
+			}
+
+			if ( wp.updates.shouldRequestFilesystemCredentials && ! wp.updates.ajaxLocked ) {
+				wp.updates.requestFilesystemCredentials( event );
+
+				$document.on( 'credential-modal-cancel', function() {
+
+					$button
+						.removeClass( 'updating-message' )
+						.text( wp.updates.l10n.installNow )
+						.attr( 'aria-label', wp.updates.l10n.installNowLabel.replace( '%s', pluginName ) );
+
+					wp.a11y.speak( wp.updates.l10n.updateCancel, 'polite' );
+				} );
 			}
 
-			wp.updates.updatePlugin( $button.data( 'plugin' ), $button.data( 'slug' ) );
+			wp.updates.installPlugin( {
+				slug:    $button.data( 'slug' ),
+				pagenow: pagenow,
+				success: wp.updates.installImporterSuccess,
+				error:   wp.updates.installImporterError
+			} );
+		} );
+
+		/**
+		 * Click handler for plugin deletions.
+		 *
+		 * @since 4.6.0
+		 *
+		 * @param {Event} event Event interface.
+		 */
+		$bulkActionForm.on( 'click', '[data-plugin] a.delete', function( event ) {
+			var $pluginRow = $( event.target ).parents( 'tr' );
+
+			event.preventDefault();
+
+			if ( ! window.confirm( wp.updates.l10n.aysDeleteUninstall.replace( '%s', $pluginRow.find( '.plugin-title strong' ).text() ) ) ) {
+				return;
+			}
+
+			wp.updates.maybeRequestFilesystemCredentials( event );
+
+			wp.updates.deletePlugin( {
+				plugin: $pluginRow.data( 'plugin' ),
+				slug:   $pluginRow.data( 'slug' )
+			} );
+
+		} );
+
+		/**
+		 * Click handler for theme updates.
+		 *
+		 * @since 4.6.0
+		 *
+		 * @param {Event} event Event interface.
+		 */
+		$document.on( 'click', '.themes-php.network-admin .update-link', function( event ) {
+			var $message  = $( event.target ),
+				$themeRow = $message.parents( 'tr' );
+
+			event.preventDefault();
+
+			if ( $message.hasClass( 'updating-message' ) || $message.hasClass( 'button-disabled' ) ) {
+				return;
+			}
+
+			wp.updates.maybeRequestFilesystemCredentials( event );
+
+			// Return the user to the input box of the theme's table row after closing the modal.
+			wp.updates.$elToReturnFocusToFromCredentialsModal = $themeRow.find( '.check-column input' );
+			wp.updates.updateTheme( {
+				slug: $themeRow.data( 'slug' )
+			} );
+		} );
+
+		/**
+		 * Click handler for theme deletions.
+		 *
+		 * @since 4.6.0
+		 *
+		 * @param {Event} event Event interface.
+		 */
+		$document.on( 'click', '.themes-php.network-admin a.delete', function( event ) {
+			var $themeRow = $( event.target ).parents( 'tr' );
+
+			event.preventDefault();
+
+			if ( ! window.confirm( wp.updates.l10n.aysDelete.replace( '%s', $themeRow.find( '.theme-title strong' ).text() ) ) ) {
+				return;
+			}
+
+			wp.updates.maybeRequestFilesystemCredentials( event );
+
+			wp.updates.deleteTheme( {
+				slug: $themeRow.data( 'slug' )
+			} );
 		} );
 
-		//
-		$( '#plugin_update_from_iframe' ).on( 'click' , function( e ) {
-			var target,	data;
+		/**
+		 * Bulk action handler for plugins and themes.
+		 *
+		 * Handles both deletions and updates.
+		 *
+		 * @since 4.6.0
+		 *
+		 * @param {Event} event Event interface.
+		 */
+		$bulkActionForm.on( 'click', '[type="submit"]:not([name="clear-recent-list"])', function( event ) {
+			var bulkAction    = $( event.target ).siblings( 'select' ).val(),
+				itemsSelected = $bulkActionForm.find( 'input[name="checked[]"]:checked' ),
+				success       = 0,
+				error         = 0,
+				errorMessages = [],
+				type, action;
+
+			// Determine which type of item we're dealing with.
+			switch ( pagenow ) {
+				case 'plugins':
+				case 'plugins-network':
+					type = 'plugin';
+					break;
+
+				case 'themes-network':
+					type = 'theme';
+					break;
+
+				default:
+					return;
+			}
+
+			// Bail if there were no items selected.
+			if ( ! itemsSelected.length ) {
+				event.preventDefault();
+				$( 'html, body' ).animate( { scrollTop: 0 } );
+
+				return wp.updates.addAdminNotice( {
+					id:        'no-items-selected',
+					className: 'notice-error is-dismissible',
+					message:   wp.updates.l10n.noItemsSelected
+				} );
+			}
+
+			// Determine the type of request we're dealing with.
+			switch ( bulkAction ) {
+				case 'update-selected':
+					action = bulkAction.replace( 'selected', type );
+					break;
+
+				case 'delete-selected':
+					if ( ! window.confirm( 'plugin' === type ? wp.updates.l10n.aysBulkDelete : wp.updates.l10n.aysBulkDeleteThemes ) ) {
+						event.preventDefault();
+						return;
+					}
+
+					action = bulkAction.replace( 'selected', type );
+					break;
+
+				default:
+					return;
+			}
+
+			wp.updates.maybeRequestFilesystemCredentials( event );
+
+			event.preventDefault();
+
+			// Un-check the bulk checkboxes.
+			$bulkActionForm.find( '.manage-column [type="checkbox"]' ).prop( 'checked', false );
+
+			$document.trigger( 'wp-' + type + '-bulk-' + bulkAction, itemsSelected );
+
+			// Find all the checkboxes which have been checked.
+			itemsSelected.each( function( index, element ) {
+				var $checkbox = $( element ),
+					$itemRow = $checkbox.parents( 'tr' );
+
+				// Only add update-able items to the update queue.
+				if ( 'update-selected' === bulkAction && ( ! $itemRow.hasClass( 'update' ) || $itemRow.find( 'notice-error' ).length ) ) {
+
+					// Un-check the box.
+					$checkbox.prop( 'checked', false );
+					return;
+				}
+
+				// Add it to the queue.
+				wp.updates.queue.push( {
+					action: action,
+					data:   {
+						plugin: $itemRow.data( 'plugin' ),
+						slug:   $itemRow.data( 'slug' )
+					}
+				} );
+			} );
+
+			// Display bulk notification for updates of any kind.
+			$document.on( 'wp-plugin-update-success wp-plugin-update-error wp-theme-update-success wp-theme-update-error', function( event, response ) {
+				var $itemRow = $( '[data-slug="' + response.slug + '"]' ),
+					$bulkActionNotice, itemName;
+
+				if ( 'wp-' + response.update + '-update-success' === event.type ) {
+					success++;
+				} else {
+					itemName = response.pluginName ? response.pluginName : $itemRow.find( '.column-primary strong' ).text();
+
+					error++;
+					errorMessages.push( itemName + ': ' + response.errorMessage );
+				}
+
+				$itemRow.find( 'input[name="checked[]"]:checked' ).prop( 'checked', false );
+
+				wp.updates.adminNotice = wp.template( 'wp-bulk-updates-admin-notice' );
+
+				wp.updates.addAdminNotice( {
+					id:            'bulk-action-notice',
+					className:     'bulk-action-notice',
+					successes:     success,
+					errors:        error,
+					errorMessages: errorMessages,
+					type:          response.update
+				} );
+
+				$bulkActionNotice = $( '#bulk-action-notice' ).on( 'click', 'button', function() {
+					// $( this ) is the clicked button, no need to get it again.
+					$( this )
+						.toggleClass( 'bulk-action-errors-collapsed' )
+						.attr( 'aria-expanded', ! $( this ).hasClass( 'bulk-action-errors-collapsed' ) );
+					// Show the errors list.
+					$bulkActionNotice.find( '.bulk-action-errors' ).toggleClass( 'hidden' );
+				} );
+
+				if ( error > 0 && ! wp.updates.queue.length ) {
+					$( 'html, body' ).animate( { scrollTop: 0 } );
+				}
+			} );
+
+			// Reset admin notice template after #bulk-action-notice was added.
+			$document.on( 'wp-updates-notice-added', function() {
+				wp.updates.adminNotice = wp.template( 'wp-updates-admin-notice' );
+			} );
+
+			// Check the queue, now that the event handlers have been added.
+			wp.updates.queueChecker();
+		} );
+
+		if ( $pluginInstallSearch.length ) {
+			$pluginInstallSearch.attr( 'aria-describedby', 'live-search-desc' );
+		}
+
+		/**
+		 * Handles changes to the plugin search box on the new-plugin page,
+		 * searching the repository dynamically.
+		 *
+		 * @since 4.6.0
+		 */
+		$pluginInstallSearch.on( 'keyup input', _.debounce( function( event, eventtype ) {
+			var $searchTab = $( '.plugin-install-search' ), data, searchLocation;
+
+			data = {
+				_ajax_nonce: wp.updates.ajaxNonce,
+				s:           event.target.value,
+				tab:         'search',
+				type:        $( '#typeselector' ).val(),
+				pagenow:     pagenow
+			};
+			searchLocation = location.href.split( '?' )[ 0 ] + '?' + $.param( _.omit( data, [ '_ajax_nonce', 'pagenow' ] ) );
 
-			target = window.parent == window ? null : window.parent,
+			// Clear on escape.
+			if ( 'keyup' === event.type && 27 === event.which ) {
+				event.target.value = '';
+			}
+
+			if ( wp.updates.searchTerm === data.s && 'typechange' !== eventtype ) {
+				return;
+			} else {
+				$pluginFilter.empty();
+				wp.updates.searchTerm = data.s;
+			}
+
+			if ( window.history && window.history.replaceState ) {
+				window.history.replaceState( null, '', searchLocation );
+			}
+
+			if ( ! $searchTab.length ) {
+				$searchTab = $( '<li class="plugin-install-search" />' )
+					.append( $( '<a />', {
+						'class': 'current',
+						'href': searchLocation,
+						'text': wp.updates.l10n.searchResultsLabel
+					} ) );
+
+				$( '.wp-filter .filter-links .current' )
+					.removeClass( 'current' )
+					.parents( '.filter-links' )
+					.prepend( $searchTab );
+
+				$pluginFilter.prev( 'p' ).remove();
+				$( '.plugins-popular-tags-wrapper' ).remove();
+			}
+
+			if ( 'undefined' !== typeof wp.updates.searchRequest ) {
+				wp.updates.searchRequest.abort();
+			}
+			$( 'body' ).addClass( 'loading-content' );
+
+			wp.updates.searchRequest = wp.ajax.post( 'search-install-plugins', data ).done( function( response ) {
+				$( 'body' ).removeClass( 'loading-content' );
+				$pluginFilter.append( response.items );
+				delete wp.updates.searchRequest;
+
+				if ( 0 === response.count ) {
+					wp.a11y.speak( wp.updates.l10n.noPluginsFound );
+				} else {
+					wp.a11y.speak( wp.updates.l10n.pluginsFound.replace( '%d', response.count ) );
+				}
+			} );
+		}, 500 ) );
+
+		if ( $pluginSearch.length ) {
+			$pluginSearch.attr( 'aria-describedby', 'live-search-desc' );
+		}
+
+		/**
+		 * Handles changes to the plugin search box on the Installed Plugins screen,
+		 * searching the plugin list dynamically.
+		 *
+		 * @since 4.6.0
+		 */
+		$pluginSearch.on( 'keyup input', _.debounce( function( event ) {
+			var data = {
+				_ajax_nonce:   wp.updates.ajaxNonce,
+				s:             event.target.value,
+				pagenow:       pagenow,
+				plugin_status: 'all'
+			},
+			queryArgs;
+
+			// Clear on escape.
+			if ( 'keyup' === event.type && 27 === event.which ) {
+				event.target.value = '';
+			}
+
+			if ( wp.updates.searchTerm === data.s ) {
+				return;
+			} else {
+				wp.updates.searchTerm = data.s;
+			}
+
+			queryArgs = _.object( _.compact( _.map( location.search.slice( 1 ).split( '&' ), function( item ) {
+				if ( item ) return item.split( '=' );
+			} ) ) );
+
+			data.plugin_status = queryArgs.plugin_status || 'all';
+
+			if ( window.history && window.history.replaceState ) {
+				window.history.replaceState( null, '', location.href.split( '?' )[ 0 ] + '?s=' + data.s + '&plugin_status=' + data.plugin_status );
+			}
+
+			if ( 'undefined' !== typeof wp.updates.searchRequest ) {
+				wp.updates.searchRequest.abort();
+			}
+
+			$bulkActionForm.empty();
+			$( 'body' ).addClass( 'loading-content' );
+			$( '.subsubsub .current' ).removeClass( 'current' );
+
+			wp.updates.searchRequest = wp.ajax.post( 'search-plugins', data ).done( function( response ) {
+
+				// Can we just ditch this whole subtitle business?
+				var $subTitle    = $( '<span />' ).addClass( 'subtitle' ).html( wp.updates.l10n.searchResults.replace( '%s', _.escape( data.s ) ) ),
+					$oldSubTitle = $( '.wrap .subtitle' );
+
+				if ( ! data.s.length ) {
+					$oldSubTitle.remove();
+					$( '.subsubsub .' + data.plugin_status + ' a' ).addClass( 'current' );
+				} else if ( $oldSubTitle.length ) {
+					$oldSubTitle.replaceWith( $subTitle );
+				} else {
+					$( '.wp-header-end' ).before( $subTitle );
+				}
+
+				$( 'body' ).removeClass( 'loading-content' );
+				$bulkActionForm.append( response.items );
+				delete wp.updates.searchRequest;
+
+				if ( 0 === response.count ) {
+					wp.a11y.speak( wp.updates.l10n.noPluginsFound );
+				} else {
+					wp.a11y.speak( wp.updates.l10n.pluginsFound.replace( '%d', response.count ) );
+				}
+			} );
+		}, 500 ) );
+
+		/**
+		 * Trigger a search event when the search form gets submitted.
+		 *
+		 * @since 4.6.0
+		 */
+		$document.on( 'submit', '.search-plugins', function( event ) {
+			event.preventDefault();
+
+			$( 'input.wp-filter-search' ).trigger( 'input' );
+		} );
+
+		/** 
+		 * Trigger a search event when the "Try Again" button is clicked. 
+		 * 
+		 * @since 4.9.0
+		 */ 
+		$document.on( 'click', '.try-again', function( event ) { 
+			event.preventDefault(); 
+			$pluginInstallSearch.trigger( 'input' ); 
+		} );
+
+		/**
+		 * Trigger a search event when the search type gets changed.
+		 *
+		 * @since 4.6.0
+		 */
+		$( '#typeselector' ).on( 'change', function() {
+			var $search = $( 'input[name="s"]' );
+
+			if ( $search.val().length ) {
+				$search.trigger( 'input', 'typechange' );
+			}
+		} );
+
+		/**
+		 * Click handler for updating a plugin from the details modal on `plugin-install.php`.
+		 *
+		 * @since 4.2.0
+		 *
+		 * @param {Event} event Event interface.
+		 */
+		$( '#plugin_update_from_iframe' ).on( 'click', function( event ) {
+			var target = window.parent === window ? null : window.parent,
+				update;
+
 			$.support.postMessage = !! window.postMessage;
 
-			if ( $.support.postMessage === false || target === null || window.parent.location.pathname.indexOf( 'update-core.php' ) !== -1 )
+			if ( false === $.support.postMessage || null === target || -1 !== window.parent.location.pathname.indexOf( 'update-core.php' ) ) {
 				return;
+			}
+
+			event.preventDefault();
 
-			e.preventDefault();
-
-			data = {
-				'action' : 'updatePlugin',
-				'slug'	 : $(this).data('slug')
+			update = {
+				action: 'update-plugin',
+				data:   {
+					plugin: $( this ).data( 'plugin' ),
+					slug:   $( this ).data( 'slug' )
+				}
 			};
 
-			target.postMessage( JSON.stringify( data ), window.location.origin );
-		});
+			target.postMessage( JSON.stringify( update ), window.location.origin );
+		} );
 
-	} );
+		/**
+		 * Click handler for installing a plugin from the details modal on `plugin-install.php`.
+		 *
+		 * @since 4.6.0
+		 *
+		 * @param {Event} event Event interface.
+		 */
+		$( '#plugin_install_from_iframe' ).on( 'click', function( event ) {
+			var target = window.parent === window ? null : window.parent,
+				install;
+
+			$.support.postMessage = !! window.postMessage;
+
+			if ( false === $.support.postMessage || null === target || -1 !== window.parent.location.pathname.indexOf( 'index.php' ) ) {
+				return;
+			}
+
+			event.preventDefault();
 
-	$( window ).on( 'message', function( e ) {
-		var event = e.originalEvent,
-			message,
-			loc = document.location,
-			expectedOrigin = loc.protocol + '//' + loc.hostname;
+			install = {
+				action: 'install-plugin',
+				data:   {
+					slug: $( this ).data( 'slug' )
+				}
+			};
+
+			target.postMessage( JSON.stringify( install ), window.location.origin );
+		} );
 
-		if ( event.origin !== expectedOrigin ) {
-			return;
-		}
-
-		message = $.parseJSON( event.data );
-
-		if ( typeof message.action === 'undefined' ) {
-			return;
-		}
+		/**
+		 * Handles postMessage events.
+		 *
+		 * @since 4.2.0
+		 * @since 4.6.0 Switched `update-plugin` action to use the queue.
+		 *
+		 * @param {Event} event Event interface.
+		 */
+		$( window ).on( 'message', function( event ) {
+			var originalEvent  = event.originalEvent,
+				expectedOrigin = document.location.protocol + '//' + document.location.hostname,
+				message;
 
-		switch (message.action){
-			case 'decrementUpdateCount' :
-				wp.updates.decrementCount( message.upgradeType );
-				break;
-			case 'updatePlugin' :
-				tb_remove();
-				if ( 'plugins' === pagenow || 'plugins-network' === pagenow ) {
-					// Return the user to the input box of the plugin's table row after closing the modal.
-					$( '#' + message.slug ).find( '.check-column input' ).focus();
-					// trigger the update
-					$( '.plugin-update-tr[data-slug="' + message.slug + '"]' ).find( '.update-link' ).trigger( 'click' );
-				} else if ( 'plugin-install' === pagenow ) {
-					$( '.plugin-card-' + message.slug ).find( 'h4 a' ).focus();
-					$( '.plugin-card-' + message.slug ).find( '[data-slug="' + message.slug + '"]' ).trigger( 'click' );
-				}
-				break;
-		}
+			if ( originalEvent.origin !== expectedOrigin ) {
+				return;
+			}
+
+			try {
+				message = $.parseJSON( originalEvent.data );
+			} catch ( e ) {
+				return;
+			}
+
+			if ( ! message || 'undefined' === typeof message.action ) {
+				return;
+			}
+
+			switch ( message.action ) {
+
+				// Called from `wp-admin/includes/class-wp-upgrader-skins.php`.
+				case 'decrementUpdateCount':
+					/** @property {string} message.upgradeType */
+					wp.updates.decrementCount( message.upgradeType );
+					break;
 
-	} );
+				case 'install-plugin':
+				case 'update-plugin':
+					/* jscs:disable requireCamelCaseOrUpperCaseIdentifiers */
+					window.tb_remove();
+					/* jscs:enable */
+
+					message.data = wp.updates._addCallbacks( message.data, message.action );
 
-	$( window ).on( 'beforeunload', wp.updates.beforeunload );
+					wp.updates.queue.push( message );
+					wp.updates.queueChecker();
+					break;
+			}
+		} );
 
-})( jQuery, window.wp, window.pagenow, window.ajaxurl );
+		/**
+		 * Adds a callback to display a warning before leaving the page.
+		 *
+		 * @since 4.2.0
+		 */
+		$( window ).on( 'beforeunload', wp.updates.beforeunload );
+	} );
+})( jQuery, window.wp, window._wpUpdatesSettings );