diff -r 48c4eec2b7e6 -r 8c2e4d02f4ef wp/wp-includes/l10n/class-wp-translation-file-mo.php
--- a/wp/wp-includes/l10n/class-wp-translation-file-mo.php	Fri Sep 05 18:40:08 2025 +0200
+++ b/wp/wp-includes/l10n/class-wp-translation-file-mo.php	Fri Sep 05 18:52:52 2025 +0200
@@ -154,7 +154,7 @@
 			// Metadata about the MO file is stored in the first translation entry.
 			if ( '' === $original ) {
 				foreach ( explode( "\n", $translation ) as $meta_line ) {
-					if ( '' === $meta_line ) {
+					if ( '' === $meta_line || ! str_contains( $meta_line, ':' ) ) {
 						continue;
 					}