Brave mobile and Vivaldi mobile have it built in. Hell, Vivaldi even has its super useful two layer tab bar available on Android.

Firefox mobile's plugin support doesn't make up for it missing other basic usability features.

Similarly, Vivaldi mobile doesn't allow custom search engines, so Brave is the only one with the minimum feature set I need (tab grouping, vertical tab bar or two layer tab bar, ad block, custom search engine, android tablet UI), and since I want to be able to sync between all my devices, I use Brave on everything.