diff --git a/firefox/TST-config.css b/firefox/TST-config.css
deleted file mode 100644
index ce4a4ef..0000000
--- a/firefox/TST-config.css
+++ /dev/null
@@ -1,27 +0,0 @@
-/* Hide border on tab bar, force its state to 'scroll', adjust margin-left for width of scrollbar. */ 
-#tabbar { border: 0; overflow-y: scroll !important; margin-left: -12px !important; scrollbar-width: auto; }
-
-/* Hide .twisty and adjust margins so favicons have 7px on left. */
-tab-item .twisty {
-    visibility: hidden;
-    margin-left: -12px;
-}
-
-/* Push tab labels slightly to the right so they're completely hidden in collapsed state */
-tab-item .label {
-    margin-left: 7px;
-}
-
-/* Hide close buttons on tabs. */
-tab-item .closebox {
-    visibility: collapse;
-}
-
-tab-item:hover .closebox {
-    visibility: initial;
-}
-
-/* Hide sound playing/muted button. */
-.sound-button::before {
-    display: none !important;
-}