diff --git a/css/leptonChrome.css b/css/leptonChrome.css
index 376d2a3..89055bd 100644
--- a/css/leptonChrome.css
+++ b/css/leptonChrome.css
@@ -5665,6 +5665,10 @@
   #tabbrowser-tabs[positionpinnedtabs] > #tabbrowser-arrowscrollbox > .tabbrowser-tab[pinned] {
     z-index: 0 !important;
   }
+  #tabbrowser-tabs[positionpinnedtabs] > #tabbrowser-arrowscrollbox > .tabbrowser-tab[pinned] .tab-stack {
+    /* Temporary solution for compatibility #513 */
+    overflow-y: clip;
+  }
 }
 /*= Selected Tab =============================================================*/
 /*= Selected Tab - Color like toolbar ========================================*/
diff --git a/src/tab/_connect_to_window.scss b/src/tab/_connect_to_window.scss
index 11ffa74..4ffcfd1 100644
--- a/src/tab/_connect_to_window.scss
+++ b/src/tab/_connect_to_window.scss
@@ -23,4 +23,9 @@
 /* Pinned Tab - tabbrowser-arrowscrollbox overflowing */
 #tabbrowser-tabs[positionpinnedtabs] > #tabbrowser-arrowscrollbox > .tabbrowser-tab[pinned] {
   z-index: 0 !important;
+
+  .tab-stack {
+    /* Temporary solution for compatibility #513 */
+    overflow-y: clip;
+  }
 }