When I access a Zoom conference via the Zoom website, Opera starts using a ton of RAM and CPU, even driving my Windows desktop up to 100% CPU. When using that feature of Zoom, I have to use Vivaldi instead, since it doesn't have that issue.
I know you are saying, why not just use the Zoom program instead? Well, I'm mainly just watching the particular conference, not participating in it, and I like to cast it to the big TV in the room. Can't cast to the TV/Nvidia Shield from Zoom, but I can from a Chromium based browser.