--- a/browser/themes/windows/compacttheme.css
+++ b/browser/themes/windows/compacttheme.css
@@ -38,26 +38,24 @@
   background-color: var(--tab-background-color);
 }
 
 #toolbar-menubar {
   text-shadow: none !important;
 }
 
 .findbar-closebutton:-moz-lwtheme-brighttext,
-#sidebar-header > .close-icon:-moz-lwtheme-brighttext,
 /* Tab styling - make sure to use an inverted icon for the selected tab
    (brighttext only covers the unselected tabs) */
 .tab-close-button[selected=true] {
   list-style-image: url("chrome://global/skin/icons/close-inverted.png");
 }
 
 @media (min-resolution: 1.1dppx) {
   .findbar-closebutton:-moz-lwtheme-brighttext,
-  #sidebar-header > .close-icon:-moz-lwtheme-brighttext,
   .tab-close-button[selected=true] {
     list-style-image: url("chrome://global/skin/icons/close-inverted@2x.png");
   }
 }
 
 /* Override tab close icon (to disable inversion) for better contrast with
    light theme on Windows 7 Classic theme. */
 @media not all and (min-resolution: 1.1dppx) {
@@ -204,24 +202,16 @@
   border-right: none !important;
 }
 
 /* Disable dragging like in the default theme: */
 #main-window[tabsintitlebar] #navigator-toolbox > toolbar:not(#toolbar-menubar):not(#TabsToolbar):-moz-lwtheme {
   -moz-window-dragging: no-drag;
 }
 
-/* The sidebar header has no background now that the background of the #browser-panel
- * has no image and is transparent. Fix: */
-.sidebar-header:-moz-lwtheme,
-#sidebar-header {
-  background-color: var(--chrome-background-color);
-  color: var(--chrome-color);
-}
-
 @media (-moz-os-version: windows-win7),
        (-moz-os-version: windows-win8) {
   /* And then we add them back on toolbars so that they don't look borderless: */
   #main-window:not([customizing])[sizemode=normal] #navigator-toolbox::after,
   #main-window:not([customizing])[sizemode=normal] #navigator-toolbox > toolbar:not(#toolbar-menubar):not(#TabsToolbar) {
     border-left: 1px solid hsla(209,67%,12%,0.35);
     border-right: 1px solid hsla(209,67%,12%,0.35);
   }