So I see "Opera GX" is a thing, and it's selling points are that you can limit CPU/Memory. I find that funny in that I do that today with systemd-run and any browser at all. Or any bloaty app.
And for the systemd-hate, that's just a wrapper around cgroups.
A nice little Mastodon instance. Mild trolling encouraged (keep it local), but not required.
Malicious behaviour is not tolerated. Follow Wheaton's law and you'll be fine.