Firefox isn't simply aping Chrome, even visually. The next UI refresh is going to look more different, not more similar. https://www.primeinspiration.com/mozilla-firefox-getting-new... The extensions API is being changed to disengage addons from the guts of the browser, which will let the team make bigger changes to CPU- and RAM-hungry areas of the codebase. The new extensions API has had a huge amount of work put into it to expand it before the old-API cutoff around November. The point is to make the browser perform better, not to make it less capable.
Whether it's the point or not, making the browser less capable is exactly what is happening.
There was a point about 7 or 8 years ago where Firefox was my favorite browser. It was the scrappy upstart that was better than IE in every single way - and look, plugins!
I had a decent plugin load, including a bunch of stuff not in the store, could skin the UI (anyone remember "Classic Compact"?) to shrink down the more annoying UI elements, use vim key bindings, and a bunch of other stuff I can't even remember anymore. I had to scroll two or three pages to list them all.
Slowly, they started taking that power away from me.
Slowly, the UI started becoming more obnoxious.
Slowly, the performance got worse and worse.
The moment Chrome got a decent ad blocker, I left and never looked back. Firefox is basically turning itself into a Chrome clone, with a side of user hostility and ancient bugs.
Thanks for the link to the themes page (I must have overlooked that and thought they blew up the theme system outright), and there are a couple of promising ones I'm looking at now.
That said, given the treatment of how some other bugs are handled, especially one particularly noxious one regarding dupe SSL certs that's been kicking around for nearly a decade now that renders Firefox unusable for technical enterprise users, the fact that it's filed in their tracker doesn't mean much, and their classification of that bug as "(REOPENED bug which will not be worked on by staff, but a patch will be accepted)" tells me that compatibility isn't that much of a priority internally.
Why not let it bake a little longer and then release it? Surely Firefox won't turn into a pumpkin if they fail to push it out the door by November?