Ticket #27797: 27797.patch

src/wp-includes/class-wp-editor.php

@@ -976 +976 @@
                 $mce_translation = apply_filters( 'wp_mce_translation', $mce_translation, $mce_locale );
 
                 foreach ( $mce_translation as $key => $value ) {
+                        // Remove strings that are not translated.
+                        if ( $key === $value ) {
+                                unset( $mce_translation[$key] );
+                                continue;
+                        }
+
                         if ( false !== strpos( $value, '&' ) ) {
                                 $mce_translation[$key] = html_entity_decode( $value, ENT_QUOTES, 'UTF-8' );
                         }