All of this crap that everyone keeps pulling into their browsers needs to be ripped back out and made a plugin or an extension. Stop shoving it in the core damn browser. I didn’t need the waste of space and I’m never going to touch it.
Of course the UI itself could be extracted into a plugin, but I'm not really a fan of the pattern of shipping a large feature and extract only the thin UI layer into a plugin. It felt very weird when Mozilla tried it with "multi-user containers".
And for many non technical users that is very useful, if they can get that with a click. To get geoblocked content, etc.
Mozilla has done way worse things, much more distracting from their core mission - building a browser that people want to use and trust.