Ticket #44308: 44308.patch

src/js/_enqueues/vendor/tinymce/plugins/wordpress/plugin.js

@@ -113 +113 @@
                                                 'alt="" title="' + title + '" data-mce-resize="false" data-mce-placeholder="1" />' );
                         }
 
-                        if ( event.load && event.format !== 'raw' && hasWpautop ) {
-                                event.content = wp.editor.autop( event.content );
+                        if ( event.load && event.format !== 'raw' ) {
+                                if ( hasWpautop ) {
+                                        event.content = wp.editor.autop( event.content );
+                                } else {
+                                        event.content = event.content.replace( /-->\s+<!--/g, '--><!--' );
+                                }
                         }
 
                         if ( event.content.indexOf( '<script' ) !== -1 || event.content.indexOf( '<style' ) !== -1 ) {
@@ -608 +612 @@
 
                 if ( hasWpautop ) {
                         event.content = wp.editor.removep( event.content );
+                } else {
+                        event.content = event.content.replace( /-->\s*<!-- wp:/g, '-->\n\n<!-- wp:' );
                 }
         });