@junyi-w Oddly enough, my Macbook Pro runs Opera with no issues, but it's an older Mac (2011), and runs High Sierra. My newer iMac, running Big Sur 11.6.1 can't run the most recent Opera for more than about five minutes, until it drives up CPU usage & uses 60 of my 64 GBs of RAM, as it instantly rises higher & higher. I must Force Quit it, or it'll freeze up my whole computer!

I have no clue why it just won't work without immediately ramping up all my CPU & RAM, and have never gotten any responses as to how to fix this, as I would very much like to use Opera on both my computers, but at this time, it's impossible.