Librewolf and IronFox (android) both work like a charm! Well, in IronFox’s case you might have to tweak JIT and WASM to ensure some niche extensions work, but I’m pretty sure it’s a me thing.

I also used Fennec (android) for a hot second, and that has extensions too.

Unfortunately it comes down to luck, you can check this crowd-sourced list to see if your banking app works. Users report whether or not they had (sandboxed) play services installed and what settings they toggled.

You won’t be able to use GPay/Wallet at all due to lack of SafetyNet.

On browser view you can’t, but I switched to desktop view and it came up. The settings page on browser is fucking embarrassing.