Sometimes it take a bit of detective work to figure out what some components do. Many of those processes that are automatically started when you log into a graphical session are initiated by a .desktop drop-in file in /etc/xdg/autostart.
Just to use your “User folders update” service as an example, I see that it has a file at /etc/xdg/autostart/user-dirs-update-gtk.desktop.
Using Fedora Linux’s rpm command, I can find the package that provides that file.
$ rpm -qf /etc/xdg/autostart/user-dirs-update-gtk.desktop
xdg-user-dirs-gtk-0.10-20.fc34.x86_64
Once I have the package name, I can list all the other files that that package contains.
$ rpm -ql xdg-user-dirs-gtk
...
/usr/share/doc/xdg-user-dirs-gtk/README
...
Looking at the README file, I get a bit more information about the package.
$ cat /usr/share/doc/xdg-user-dirs-gtk/README
xdg-user-dirs-gtk is a companion to xdg-user-dirs that integrates it into
the Gnome desktop and Gtk+ applications.
It gets run during login and does two things:
* Tracks changes of locale and prompts the user so the directories
can be changed.
* Creates a default gtk bookmarks file if there is none, based
on a set of xdg user dirs.
Then I can do the same for stated “companion” package xdg-user-dirs which eventually leads me to a link to online documentation.
https://freedesktop.org/wiki/Software/xdg-user-dirs/
Hope that helps.
P.S. sssd shouldn’t be necessary if you have a local account in /etc/passwd.