diff --git a/userChrome.css b/userChrome.css
index 8e60300..2753894 100644
--- a/userChrome.css
+++ b/userChrome.css
@@ -328,11 +328,7 @@
   }
 
   /** Unselected Tab - Divide line ********************************************/
-  .titlebar-spacer[type="pre-tabs"] {
-    border-inline-end: 1px solid var(--lwt-background-tab-separator-color, currentColor);
-    opacity: 0.3;
-  }
-
+  .tabbrowser-tab[first-visible-tab]::before,
   .tabbrowser-tab::after, #tabbrowser-tabs[movingtab] > #tabbrowser-arrowscrollbox > .tabbrowser-tab[visuallyselected]::before {
     content: "";
     display: block;
@@ -345,13 +341,18 @@
   .tabbrowser-tab::before {
     margin-inline-start: -1px !important;
   }
+  .tabbrowser-tab[first-visible-tab]::before {
+    border-right: 1px solid var(--lwt-background-tab-separator-color, currentColor) !important;
+  }
 
+  .tabbrowser-tab[first-visible-tab]::before,
   :root[tabsintitlebar]:not([extradragspace]) #toolbar-menubar[autohide="true"] + #TabsToolbar .tabbrowser-tab::after, .tabbrowser-tab:hover::after, #tabbrowser-tabs:not([movingtab]) > #tabbrowser-arrowscrollbox > .tabbrowser-tab[beforehovered]::after, .tabbrowser-tab[multiselected]::after, #tabbrowser-tabs:not([movingtab]) > #tabbrowser-arrowscrollbox > .tabbrowser-tab[before-multiselected]::after {
     margin-top: var(--tabs-top-border-width) !important;
     margin-bottom: 0 !important;
   }
 
   /* Selected - Hide */
+  .tabbrowser-tab[first-visible-tab][visuallyselected]::before,
   #tabbrowser-tabs:not([movingtab]) > #tabbrowser-arrowscrollbox > .tabbrowser-tab[beforeselected-visible]::after, #tabbrowser-tabs[movingtab] > #tabbrowser-arrowscrollbox > .tabbrowser-tab[visuallyselected]::before, .tabbrowser-tab[visuallyselected]::after {
     border-color: var(--tabs-border-color) !important;
     margin-top: 0 !important;