Does Librewolf support multiple profiles like Firefox? If so that’s how I’ve always done it on Firefox. One Firefox install, multiple concurrent profiles. I even use Container Tabs on top of that.
“The -no-remote flag allows multiple firefox profiles to run at the same time.” https://askubuntu.com/questions/660147/how-can-i-use-two-firefox-profiles
to catch them is my real test
to train them is my cause