diff --git a/devtools/client/themes/floating-scrollbars-dark-theme.css b/devtools/client/themes/floating-scrollbars-dark-theme.css
index b39dbce07ea3..45b8fbe09f70 100644
--- a/devtools/client/themes/floating-scrollbars-dark-theme.css
+++ b/devtools/client/themes/floating-scrollbars-dark-theme.css
@@ -15,6 +15,7 @@
   padding: 2px;
 }
 
+*|*:root[platform="mac"] > scrollbar,
 *|*:root[platform="mac"] *|*:not(html|select) > scrollbar {
   border: none;
 }
@@ -40,10 +41,15 @@
   border-radius: 3px !important;
 }
 
+*|*:root[platform="mac"] > scrollbar slider,
 *|*:root[platform="mac"] *|*:not(html|select) > scrollbar slider {
   -moz-appearance: none !important;
 }
 
+*|*:root[platform="win"] > scrollbar scrollbarbutton,
+*|*:root[platform="linux"] > scrollbar scrollbarbutton,
+*|*:root[platform="win"] > scrollbar gripper,
+*|*:root[platform="linux"] > scrollbar gripper,
 *|*:root[platform="win"] *|*:not(html|select) > scrollbar scrollbarbutton,
 *|*:root[platform="linux"] *|*:not(html|select) > scrollbar scrollbarbutton,
 *|*:root[platform="win"] *|*:not(html|select) > scrollbar gripper,