I am not able to replicate this issue. To be clear (in both Plasma Wayland and X sessions), all of my notifications for system, apps like Thunderbird emails, and KDE Connect messages from my phone all show up under the notifications menu in the KDE system tray and I am able to close them individually or in groups by clicking the X in the top right corner of each message or group of messages.
I would set up a new user and try to see if the issue is replicated. If it is, then this eliminates personalization and configuration issues like misbehaving plasmoids, themes, etc.
If you still have issues it might help to see your make.conf.
Did you install plasma as the default all purpose kde-plasma/plasma-meta?
What is your graphics setup, driver etc?
It sometimes helps with these kinds of theme issues to delete (or temporarily move) the files in cache from the command line when not logged in to a KDE session. This can be done in a TTY when the SDDM login screen is displayed. This is generally harmless and the files should be recreated on login. You can check to see if it made any difference after logging in again.
In order to do this last option, you would need to have kde-plasma/plasma-sdk installed.
Since the system tray and the notifications service, specifically KDE's Status Notifier Manager, is already running and connected to DBUS, trying to run a second instance will fail and it will only give you limited information but you can try it anyway to see if there is any helpful output.
From the terminal, you can run:
Code: Select all
plasmoidviewer -a org.kde.plasma.notifications
and
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plasmoidviewer --applet org.kde.plasma.systemtray
to see if there is any helpful messages or output.
From the last one, you can click on the notifications icon in the system tray and observe the output in the terminal. If the notifications icon is not visible it may be hidden and you would need to click on the arrow for "show hidden icons" in the system tray to access it.