On Emacs 27.2 I am trying to get notifications to work on my KDE desktop. Please note that notifications work just fine on my XFCE desktop.

I can reproduce the issue easily:

ELISP> (notifications-notify)

Which produces the following error message:

Error: (dbus-error "No connection to bus" session)

I have tried to run dbus-launch before starting emacs but I get the same behavior.

I have tried to (setq alert-default-style 'libnotify) but this also does not do anything.

Any ideas on what the problem is?

EDIT:

I have partially solved the problem, though the problem is not with Emacs so this is no longer the best place for support. Anyways ...

If I run:

$ export DBUS_SESSION_BUS_ADDRESS
$ emacs

Then (notifications-notify) works as intended!

However I cannot figure out how to export this variable for the entire KDE session. I tried to put export DBUS_SESSION_BUS_ADDRESS after the exec startplasma-x11 line in my ~/.xinitrc but that did not work.

EDIT2:

I got it to work by launching kde with startx with the following in my ~/.xinitrc.

exec dbus-launch --exit-with-session startplasma-x11

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