Fix “new items glow” being displayed above settings and announcements (#12958)

app/javascript/mastodon/components/column_header.js

@@ -33,6 +33,7 @@ class ColumnHeader extends React.PureComponent {
     onPin: PropTypes.func,
     onMove: PropTypes.func,
     onClick: PropTypes.func,
+    appendContent: PropTypes.node,
   };
 
   state = {
@@ -81,7 +82,7 @@ class ColumnHeader extends React.PureComponent {
   }
 
   render () {
-    const { title, icon, active, children, pinned, multiColumn, extraButton, showBackButton, intl: { formatMessage }, placeholder } = this.props;
+    const { title, icon, active, children, pinned, multiColumn, extraButton, showBackButton, intl: { formatMessage }, placeholder, appendContent } = this.props;
     const { collapsed, animating } = this.state;
 
     const wrapperClassName = classNames('column-header__wrapper', {
@@ -172,6 +173,8 @@ class ColumnHeader extends React.PureComponent {
             {(!collapsed || animating) && collapsedContent}
           </div>
         </div>
+
+        {appendContent}
       </div>
     );
 

app/javascript/mastodon/features/home_timeline/index.js

@@ -143,12 +143,11 @@ class HomeTimeline extends React.PureComponent {
           pinned={pinned}
           multiColumn={multiColumn}
           extraButton={announcementsButton}
+          appendContent={hasAnnouncements && showAnnouncements && <AnnouncementsContainer />}
         >
           <ColumnSettingsContainer />
         </ColumnHeader>
 
-        {hasAnnouncements && showAnnouncements && <AnnouncementsContainer />}
-
         <StatusListContainer
           trackScroll={!pinned}
           scrollKey={`home_timeline-${columnId}`}

app/javascript/styles/mastodon/components.scss

@@ -3224,13 +3224,16 @@ a.status-card.compact:hover {
 .column-header__wrapper {
   position: relative;
   flex: 0 0 auto;
+  z-index: 1;
 
   &.active {
+    box-shadow: 0 1px 0 rgba($highlight-text-color, 0.3);
+
     &::before {
       display: block;
       content: "";
       position: absolute;
-      top: 35px;
+      bottom: -13px;
       left: 0;
       right: 0;
       margin: 0 auto;
@@ -3241,6 +3244,11 @@ a.status-card.compact:hover {
       background: radial-gradient(ellipse, rgba($ui-highlight-color, 0.23) 0%, rgba($ui-highlight-color, 0) 60%);
     }
   }
+
+  .announcements {
+    z-index: 1;
+    position: relative;
+  }
 }
 
 .column-header {
@@ -3273,8 +3281,6 @@ a.status-card.compact:hover {
   }
 
   &.active {
-    box-shadow: 0 1px 0 rgba($highlight-text-color, 0.3);
-
     .column-header__icon {
       color: $highlight-text-color;
       text-shadow: 0 0 10px rgba($highlight-text-color, 0.4);
@@ -3330,6 +3336,8 @@ a.status-card.compact:hover {
   color: $darker-text-color;
   transition: max-height 150ms ease-in-out, opacity 300ms linear;
   opacity: 1;
+  z-index: 1;
+  position: relative;
 
   &.collapsed {
     max-height: 0;