apparmor comes with several profiles, and if in your distro it doesn’t include one for librewolf, you can use the firefox one. And if there’s no available one and you would be interested in combine it with firejail then most probably firejail will come with with a profile for firefox or librewolf and usually with support for apparmor. Regardless of the distros, the arch wiki can guide you with apparmor and firejail. I recommend becoming familiar with both. Another option if there’s no profile on your distro is to look into another distro’s profile. ubuntu used include some software with apparmor out of the box so perhaps it’s a good source of profiles…

Also in this same community there’s an old post precisely about what you’re asking for, though it’s a bit dated, you may want to scroll for some time until getting to it.