Hi, I'm not familiar with it myself, but have a look in [https://addons.mozilla.org/en-US/firefox/addon/ublock-origin/?src=ss uBlock Origin]'s Options - Add-ons Manager (Ctrl+Shift+A) > Extensions. You could instead try dragging its button into the 3-bar menu (while in Customize mode) [[Customize Firefox controls, buttons and toolbars]]. ''If your question is resolved by this or another answer, please take a minute to let us know. Thank you!''