Fix source code control buttons

rstudio/_rstudio-dark.scss

   }
 }
 
+.rstudio-themes-flat .rstudio-themes-dark-grey {
+  div.windowframe > div:last-child > div > div > div > div > div:not(.gwt-TabLayoutPanelTabs) {
+    /* hacky toolbars section */
+    background: $ui-rstudio-tabs-inactive !important;
+  }
+}
+
 /* scrollbars */
 .rstudio-themes-flat .rstudio-themes-dark-grey .gwt-TabLayoutPanelTabs,
 .rstudio-themes-flat .rstudio-themes-dark-grey .rstheme_minimizedWindowObject .rstheme_center,