From 4b1a6db6d23e35a0c7f21cff1df788e4ad181a4f Mon Sep 17 00:00:00 2001
From: MrOtherGuy <jastekken@outlook.com>
Date: Fri, 11 Oct 2019 08:20:35 +0300
Subject: [PATCH] Use generic scrollbox[horizontal] selectors to target Firefox
 71+

---
 chrome/multi-row_tabs.css | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/chrome/multi-row_tabs.css b/chrome/multi-row_tabs.css
index e5a862f..24bbe4e 100644
--- a/chrome/multi-row_tabs.css
+++ b/chrome/multi-row_tabs.css
@@ -18,6 +18,20 @@
   min-height: unset !important;
   padding-inline-start: 0px !important
 }
+/* Selectors for Firefox 71+ */
+/* These are not tabs toolbar specific but horizontal scrollbox isn't used elsewhere, except in bookmarks toolbar but there it doesn't have [part] attribute since it's not in shadow-root */
+.scrollbutton-up[orient="horizontal"][part]~spacer,
+.scrollbutton-up[orient="horizontal"][part],
+.scrollbutton-down[orient="horizontal"][part]{ display: none }
+
+scrollbox[part][orient="horizontal"]{
+  display: flex;
+  flex-wrap: wrap;
+  overflow-y: auto;
+  max-height: calc(var(--tab-min-height) * var(--multirow-n-rows));
+  scrollbar-color: currentColor transparent;
+  scrollbar-width: thin;
+}
 
 /* Test for Firefox > 66 */
 @supports (inset-block:auto){