Ticket #29492: 29492.2.patch

src/wp-admin/js/editor-expand.js

@@ -31 +31 @@
                         fixedSideTop = false,
                         fixedSideBottom = false,
                         scrollTimer,
+                        scrollRatio = 0,
                         lastScrollPosition = 0,
                         pageYOffsetAtTop = 130,
                         pinnedToolsTop = 56,
@@ -255 +256 @@
                                 setTimeout( function() {
                                         editor.execCommand( 'wpAutoResize' );
                                         adjust();
+
+                                        if ( scrollRatio ) {
+                                                window.scrollTo( window.pageXOffset, $document.height() * scrollRatio );
+                                                scrollRatio = 0;
+                                        }
                                 }, 300 );
                         }
 
@@ -270 +276 @@
 
                                         textEditorResize();
                                         adjust();
+
+                                        if ( scrollRatio ) {
+                                                window.scrollTo( window.pageXOffset, $document.height() * scrollRatio );
+                                                scrollRatio = 0;
+                                        }
                                 }, 100 );
 
                                 adjust();
@@ -622 +633 @@
                         scrollTimer = setTimeout( adjust, 100 );
                 }
 
+                function getScrollRatio() {
+                        if ( lastScrollPosition ) {
+                                scrollRatio = lastScrollPosition / $document.height();
+                        } else {
+                                scrollRatio = 0;
+                        }
+                }
+
                 function on() {
                         // Scroll to the top when triggering this from JS.
                         // Ensures toolbars are pinned properly.
@@ -629 +648 @@
                                 window.scrollTo( window.pageXOffset, 0 );
                         }
 
-                        $wrap.addClass( 'wp-editor-expand' );
+                        $wrap.addClass( 'wp-editor-expand' ).on( 'mousedown.editor-expand', '.wp-switch-editor', getScrollRatio );
 
                         // Adjust when the window is scrolled or resized.
                         $window.on( 'scroll.editor-expand resize.editor-expand', function( event ) {
@@ -690 +709 @@
                                 window.scrollTo( window.pageXOffset, 0 );
                         }
 
-                        $wrap.removeClass( 'wp-editor-expand' );
+                        $wrap.removeClass( 'wp-editor-expand' ).off( 'mousedown.editor-expand' );
 
                         $window.off( '.editor-expand' );
                         $document.off( '.editor-expand' );