If you are reusing a profile, delete it and see if it is profile related. Your profile is in your home directory, just delete the .mozilla directory and launch Firefox again. If that doesn’t work, try out the flatpak version of Firefox as all dependencies are included.
faced this problem on a fresh install of fedora silverblue, fedora kinoite & fedora gnome.
this problem occurs only the 1st time post installation when i delete all the preset fedora / red hat bookmarks & install my own bookmarks via an html file.
i prefer getting my apps from fedora repositories, no flatpaks.
as reported in the bug & by me earlier firefox only crashes after a fresh install the first time i delete all default bookmarks & never after that so i guess i can live with that.
i prefer not make changes to the defaults in about:config.