Ticket #38850: 38850.2.patch

src/wp-admin/css/edit.css

@@ -379 +379 @@
         border-bottom: 0 none;
 }
 
-.wp-editor-expand div.mce-statusbar {
+.wp-editor-expand.toolbar-open div.mce-statusbar {
         z-index: 1;
+        position: sticky;
+        position: -webkit-sticky;
+        bottom: 23px; /* #post-status-info: height + border-top */
 }
 
-.wp-editor-expand #post-status-info {
+.wp-editor-expand.toolbar-open #post-status-info {
         border-top: 1px solid #e5e5e5;
+        position: sticky;
+        position: -webkit-sticky;
+        bottom: -1px; /* border-bottom */
 }
 
 .wp-editor-expand div.mce-toolbar-grp {
         z-index: 999;
 }
 
+.wp-editor-expand .wp-editor-tools {
+        position: sticky;
+        position: -webkit-sticky;
+        top: 32px;
+}
+
+.wp-editor-expand div.mce-toolbar-grp,
+.wp-editor-expand .quicktags-toolbar {
+        position: sticky;
+        position: -webkit-sticky;
+        top: 87px; /* admin bar height + tools height */
+}
+
 /* TinyMCE native fullscreen mode override */
 .mce-fullscreen #wp-content-wrap .mce-menubar,
 .mce-fullscreen #wp-content-wrap .mce-toolbar-grp,

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

@@ -6 +6 @@
                 $adminBar = $( '#wpadminbar' ),
                 $footer = $( '#wpfooter' );
 
+        var featureSticky = ( function() {
+                var element = document.createElement( 'div' );
+                var style = element.style;
+
+                style.cssText = 'position:sticky;position:-webkit-sticky';
+
+                return !! style.position;
+        } )();
+
         /* Autoresize editor. */
         $( function() {
                 var $wrap = $( '#postdivrich' ),
@@ -323 +332 @@
                                 return;
                         }
 
+                        if ( ! featureSticky ) {
+
                         topPos = $top.parent().offset().top;
                         editorPos = $editor.offset().top;
                         editorHeight = $editor.outerHeight();
@@ -468 +479 @@
                                 }
                         }
 
+                        } // end ! featureSticky
+
                         // Sidebar pinning
                         if ( $postboxContainer.width() < 300 && heights.windowWidth > 600 && // sidebar position is changed with @media from CSS, make sure it is on the side
                                 $document.height() > ( $sideSortables.height() + postBodyTop + 120 ) && // the sidebar is not the tallest element
@@ -558 +571 @@
                                 fixedSideTop = fixedSideBottom = false;
                         }
 
-                        if ( resize ) {
+                        if ( resize && ! featureSticky ) {
                                 $contentWrap.css( {
                                         paddingTop: heights.toolsHeight
                                 } );

src/wp-includes/js/tinymce/plugins/wordpress/plugin.js

@@ -62 +62 @@
                         }
                 }
 
+                if ( editor.id === 'content' ) {
+                        tinymce.$( '#postdivrich' ).toggleClass( 'toolbar-open', state !== 'hide' )
+                }
+
                 editor.fire( 'wp-toolbar-toggle' );
         }
 
@@ -72 +76 @@
                 onPostRender: function() {
                         wpAdvButton = this;
                         wpAdvButton.active( getUserSetting( 'hidetb' ) === '1' ? true : false );
+                        tinymce.$( '#postdivrich' ).toggleClass( 'toolbar-open', getUserSetting( 'hidetb' ) === '1' )
                 }
         });