This is apparent from the service file directory in plymouth:
├── multi-user.target.wants
│   ├── plymouth-quit.service -> ../plymouth-quit.service
│   └── plymouth-quit-wait.service -> ../plymouth-quit-wait.service

Leaving it unspecified caused gdm-wayland to crash on boot, see #39615.

The change made other display managers not quit plymouth properly however. By
removing "multi-user.target" from `plymouth-quit.after` this is resolved.

Semi-automatic update generated by https://github.com/ryantm/nixpkgs-update tools.

This update was made based on information from https://repology.org/metapackage/metabase/versions.

These checks were done:

- built on NixOS
- Warning: no binary found that responded to help or version flags. (This warning appears even if the package isn't expected to have binaries.)
- directory tree listing: https://gist.github.com/40a08752e83dd27b03a5e553c6f89582
- du listing: https://gist.github.com/fe6508f6abc39c37b41465ae8e9efd81

http://git.savannah.gnu.org/cgit/nano.git/tree/ChangeLog?h=v2.9.7

atom: 1.26.1 -> 1.27.0

nano: 2.9.4 -> 2.9.7

handbrake: platforms: linux -> unix; rm cmake dep

Make plymouth work with gdm wayland

psppire needs to be wrapped so that it will work outside of GNOME
desktop. We provide hicolor-icon-theme & gsettings-desktop-schemas.

Note that at runtime, I still get this error:

- Cannot create a converter for `IBM864' to `UTF-8': Invalid argument

Possibly a locale issue.

Fixes #40558