--- a/browser/themes/osx/browser.css
+++ b/browser/themes/osx/browser.css
@@ -1566,18 +1566,17 @@ toolbarbutton.chevron > .toolbarbutton-m
 
 #TabsToolbar:not(:-moz-lwtheme) {
   color: #333;
   text-shadow: @loweredShadow@;
 }
 
 %ifdef MOZ_PHOTON_THEME
 :root:-moz-any([inFullscreen], [tabsintitlebar]) #TabsToolbar:not(:-moz-lwtheme) {
-  -moz-appearance: none;
-  background-color: #232323;
+  -moz-appearance: -moz-mac-vibrancy-dark;
   color: hsl(240, 9%, 98%);
   text-shadow: none;
 }
 %endif
 
 %ifndef MOZ_PHOTON_THEME
 #navigator-toolbox[inFullscreen] > #TabsToolbar {
   padding-top: var(--space-above-tabbar);