* Why somethings are missing?
Guix is managed *per-user* , so one must do most things per-user
depending on what must be done. Of course, somethings aren't needed,
e.g.: Installing graphical programs or icon themes for root user
(because root user doesn't really use these that much).
* Regarding missing icons
Install "adwaita-icon-theme" and "hicolor-icon-theme" from Guix, then
make a symbolic link to the resulting "Adwaita" and "hicolor"
directories (that are inside the user's Guix profile), like so:
(Note: remember to use `ln` with the `-s`/`--symbolic` option, and keep
paths relative so that things are easier to move around to other
computers or users, that is, remember to use the the triple "../" shown
$ cd ".local/share/icons"
$ ln -s "../../../.guix-profile/share/icons/Adwaita"
$ ln -s "../../../.guix-profile/share/icons/hicolor"
* Missing application launchers in the menu
After installing an application, their .desktop files (application
launchers) are available in "$GUIX_PROFILE/share/applications".
For example, suppose I just installed GnuCash and Icecat for my current
user, then I do:
$ cd ".local/share/applications"
$ ln -s "../../../.guix-profile/share/applications/gnucash.desktop"
$ ln -s "../../../.guix-profile/share/applications/icecat.desktop"
Some applications still don't have the .desktop file, or it's not doing
all that it's supposed to do (e.g.: *Suppose* VLC doesn't appear in the
"Open with" right-mouse menu when clicking on some files, then this
might be an issue with the vlc.desktop file, or with your user's "mime"*
files in the same directory (".local/share/applications") or in
"/usr/share/applications", or in some other place people knowledgeable
of customization might have to englighten us. ;)