Yep, apparently. (Technically not macOS, but OS X, since I haven't upgraded from El Capitan just yet.) I'd never had an issue with frequent kernel panics before

Yep, apparently. (Technically not macOS, but OS X, since I haven't upgraded from El Capitan just yet.) I'd never had an issue with frequent kernel panics before, so I'm not sure what could be up with videos in Firefox.