Whereas www-client/librewolf-bin-116.0.3_p1 has it own. Desktop files are both displaying fine though...
www-client/librewolf does not exist in the gentoo repo. If this bug report was intended for an overlay, please update the bug summary with the overlay name and change the bug status to UNCONFIRMED.
It is indeed from an overlay as described in: https://wiki.gentoo.org/wiki/LibreWolf
That overlay is not listed on overlays.gentoo.org, so I have no way to identify a maintainer. Please report bugs to whoever runs that overlay.
This appears to be their issue tracker: https://codeberg.org/librewolf/issues/issues