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4 browsers that will continue to support uBlock Origin and other ad blockers with Manifest V2
(www.xda-developers.com)
This is a most excellent place for technology news and articles.
Tab stacks and mouse gestures are the 2 that I use the most, that don't exist in Firefox. Tab hibernation is also extremely useful, but I don't know if that exists in Firefox.
And in general there are so many useful tools, like bookmarking by stack and/or window etc.