diff -r 07239de796bb -r e756a8c72c3d cms/drupal/misc/textarea.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cms/drupal/misc/textarea.js	Fri Sep 08 12:04:06 2017 +0200
@@ -0,0 +1,32 @@
+(function ($) {
+
+Drupal.behaviors.textarea = {
+  attach: function (context, settings) {
+    $('.form-textarea-wrapper.resizable', context).once('textarea', function () {
+      var staticOffset = null;
+      var textarea = $(this).addClass('resizable-textarea').find('textarea');
+      var grippie = $('<div class="grippie"></div>').mousedown(startDrag);
+
+      grippie.insertAfter(textarea);
+
+      function startDrag(e) {
+        staticOffset = textarea.height() - e.pageY;
+        textarea.css('opacity', 0.25);
+        $(document).mousemove(performDrag).mouseup(endDrag);
+        return false;
+      }
+
+      function performDrag(e) {
+        textarea.height(Math.max(32, staticOffset + e.pageY) + 'px');
+        return false;
+      }
+
+      function endDrag(e) {
+        $(document).unbind('mousemove', performDrag).unbind('mouseup', endDrag);
+        textarea.css('opacity', 1);
+      }
+    });
+  }
+};
+
+})(jQuery);