diff --git a/chrome/centered_tab_label.css b/chrome/centered_tab_label.css
index 4166f7f..6ee51af 100644
--- a/chrome/centered_tab_label.css
+++ b/chrome/centered_tab_label.css
@@ -1,7 +1,20 @@
 /* Source file https://github.com/MrOtherGuy/firefox-csshacks/tree/master/chrome/centered_tab_label.css made available under Mozilla Public License v. 2.0
 See the above repository for updates as well as full license text. */
 
-.tab-label-container{ display: grid; justify-content: safe center; align-items: safe center; }
-.tab-label,.tab-secondary-label{ overflow: hidden }
-.tabbrowser-tab[selected]:not(:hover) .tab-label-container,
-#tabbrowser-tabs:not([closebuttons="activetab"]) .tabbrowser-tab:not(:hover,[pinned]) .tab-label-container{ margin-inline-end: 7px }
+.tab-label-container{
+  display: grid;
+  justify-content: safe center;
+  align-items: safe center;
+}
+
+.tab-secondary-label{
+  -moz-box-pack: center;
+}
+
+.tab-label,
+.tab-secondary-label{ overflow: hidden }
+
+.tabbrowser-tab[selected]:not(:hover) .tab-label-container:not([labeldirection="rtl"]),
+#tabbrowser-tabs:not([closebuttons="activetab"]) .tabbrowser-tab:not(:hover,[pinned]) .tab-label-container:not([labeldirection="rtl"]){
+  margin-inline-end: 7px;
+}