Mostly LibreWolf, but I’ve been enjoying Zen Browser recently. It’s based on Firefox but with lots of cool extra functionality baked in. It is still in alpha though and I’ve experienced some bugs, including it crashing my whole system a couple of times, but it’s very promising
Random applications that use the play integrity API won’t work on any third party OSes or ROMs. For example I tried to install some Intuit app on my GOS Pixel a while back (credit karma I think?) and it didn’t work at all