Apparently the interactive CPU governor is buggy. I changed it to performance, and now Firefox is fast. I bought SetCPU and told it to change the governor to performance when the screen turns on and back to interactive when the screen is off. Don’t care if it’s slow when not using it.
Sweet, might not need a new phone now. But what am I supposed to buy then? Nothing? Boohoo.
I already had my phone rooted, super easy to do, you just click one button after opening the program. Now I don’t need a new phone for years.