The package has a debian/watch file, but the last attempt
to use it for checking for newer upstream versions failed with
an error:
In debian/watch no matching files for watch line https://gitlab.com/arcmenu/ArcMenu/tags?sort=updated_desc (?:.*/)ArcMenu-v(?:[-_]?[Vv]?(\d[\-+\.:\~\da-zA-Z]*))\.tar\.gz
testing migration
This package will soon be part of the gnome-shell-46 transition. You might want to ensure that your package is ready for it.
You can probably find supplementary information in the
debian-release
archives or in the corresponding
release.debian.org
bug.