Yesterday my roku kept crashing. So I went and bought a new one thinking that was the issue. (Until doing research I had no clue this was a common issue). I now have the roku express 4k. It still continues to crash despite restarting and clearing catch like I have read. I have deleted multiple apps. And it does not matter if I am watching Netflix, Disney plus, or simply am on the home screen. I am unsure of what else to try or do.
If you are using the TV USB port for power, try using a USB power adapter at a wall outlet instead. (any 5volt, 1 amp cell phone charging adapter should work).
Yeah, I learned that the hard way when I attempted to plug my Roku Express directly into the TV USB power port when using it at a hotel, and things went wonky with it -- I couldn't get it to connect to the network and it would freeze up. Next time I know to bring an extension cord because outlets were in limited supply, but when I plugged my express into an outlet, everything just worked.