Hello @Romaing6969
did you tried to read the log to check what happened
could you try journalctl -p err | grep brave
or any log option you have on Manjaro
you could also reinstall it using the pacman
and try to create temprary profile using the following method
of it work fine then open it normally if the issue show up again then the issue with the profile
by the way reinstall does not remove brave data so in case if the issue with your profiles uninstall brave will keep the profile folder there so when you reinstall it will launch that old profiles
hope that your data in that old profile is saved like your bookmark and password and others
if they saved somewhere else then you can delete the old data profile
which you can find here
hope any of those help and have a nice day 