Easiest way is to use Chrome or a Chrome based browser since they bundle codecs with the browser. If you're using Firefox, need to make sure you have the codecs. I know nothing about Mint specifically though to know if they'd automatically install codecs or not.
You specifically don't want to use the bundled codecs since those would be CPU decode only.
Interesting. I'll look into that more.
Im using Brave and it seems the enable hardware acceleration box is checked.