Kubuntu Software Center in 24.04 won't start

[tomwitt]

I recently upgrade from 22.04 to 24.04. I'm now trying to update VSCode and it very much wants me to use the software center rather than install the Debian package I downloaded. Fair enough.

Trying to start the software center via icon just results in a spinning button. Examining the icon contents (Right click, Edit Application), I can see that it's calling "plasma-discover". Running this at the command line does nothing.

I'm not sure how to go about fixing this.

Edit 1:

After a long wait, running plasma-discover from the command line gives this error

kf.dbusaddons: Couldn't register name 'org.kde.discover' with DBUS - another process owns it already!

Edit 2:

This prior bug report exactly mirrors what is currently happening.
https://askubuntu.com/questions/1514...-open-discover

The suggested workaround does work for me

pkill discover
plasma-discover --backends packagekit-backend​

[tomwitt]

It's now a couple of months later and Software Center (plasma-discover) is still a mess. Supposedly it's fixed in KDE 6.0.1(3). I'm hoping this gets fixed soon.

[Snowhog]

Try installing/reinstalling the components of Discover Software Center.

Open Konsole and type:
sudo apt-get install --reinstall plasma-discover-common plasma-discover-backend-fwupd plasma-discover-backend-snap plasma-discover-notifier plasma-discover

[MDRMustang]

I updated to 22.04 to 24.04 yesterday and same issue. Discover will not start. Tried the above suggestion to reinstall plasma, no luck. Any other ideas on this issue?

One other alternative to the OP would be to try to update using Synaptic. It works fine for me.

EDIT: I just noticed the OPs workaround. That did work to bring up Discover, but it still doesn't start from the command line.

[vanadiumboy]

My rant:

There are some important aspects of Linux (the entire Linux world) that are going unfixed.
To all programmers:
Never, ever, post something to the console without letting the user know.
If you are going to make a CLI application, make a CLI application.
If you are going to make a GUI application, learn to make a GUI application.
The CLI world and the GUI world are 2 separate worlds.

For your GUI application, post a message in a ............ MessageBox!
And always let the user know what the application is doing. Don’t show just a progress bar that advances and then stops at 90% for an hour.

[pwl1024]

Tried both Snowhog and tomwitt suggestions but no luck. Has anybody had any progress on this ?
Ta

[Quantumcat]

(Newbie to the Forum Here.) I did a fresh install of Kubuntu 24.04 about two weeks ago from a live USB that I set up the same day. The Discover Software Center was opening at first. I used it to download software. However, now it won't open. I just get a spinning image over the icon in the Task Manager. The code suggestion from the original post did work...

pkill discover
plasma-discover --backends packagekit-backend​​

but only for a one-off opening of Discover. It's not a fix of Discover and the problem that Discover doesn't open when the icon is clicked. I'm just posting to find out whether someone knows of any progress here, or if someone has some understanding of what is causing the issue. (I can get by without Discover by using the command line to do periodic updates if need be or by using the Snap Store or some other software app. However, it is irritating that the Software Center and Update Notifications of the distro aren't working properly. I'm curious if there's an easy fix.)

[Minna]

I have the same problem with a fresh installation.

Notably, the very first run did work fine. It did install updates.
On the second run the window opened, just to close immediately after.

Since then, it's the same behaviour as described elsewhere: a spinning wheel and then nothing.
Starting

plasma-discover

from the command line produces:

fetch ratings! true
adding empty sources model QStandardItemModel(0x5a31f2fe8960)

and nothing more.

journalctl -f

produced no meaningful output in neither case.

Note: I have been using KDE since version 1.0 and Kubuntu for more than a decade, five years on this machine.

Never have I ever experienced something similar.

[Qqmike]

I find this interesting because recently I had the same issue with Discover in 22.04, but the problem stopped after a restart.

https://www.kubuntuforums.net/forum/...-with-discover

What's really interesting is that no one chimed in with a fix! ha-ha

What a coincidence?

[Snowhog]

Notably, the very first run did work fine. It did install updates.
On the second run the window opened, just to close immediately after.

After the "install updates.", did you log out/log back in and/or reboot? Some updates require a restart to finish package changes.

[Minna]

After the "install updates.", did you log out/log back in and/or reboot? Some updates require a restart to finish package changes.

Of course. Several times.

The issue won't disappear.

Of course, I can install software und update the system from the command line, but that's not the point of a Desktop environment.

I noticed, that

notepadqq

has the same issue, so it's probably a Qt issue. This is, what several recent Arch and Debian forum entries about not starting Discover, suggest. However, none did provide a working solution.

In the Qt forums, newer entries with this issue are always closed and backlinked to older occurrences of the same issue, which are then marked as "closed".


Edit: The other programs, I have used so far on this fresh install (Firefox, the System Monitor, Konsole and Kate) all work perfectly.

[Minna]

... but the problem stopped after a restart. ...

A problem that can be solved by reinstalling a package and rebooting isn't a problem. It's just Linux

[Qqmike]

A problem that can be solved by reinstalling a package and rebooting isn't a problem. It's just Linux

Yeah, I (might) agree. 😉
But in this case (mine), Discover was working perfectly since I first installed 22.04.
Then one day I got the usual update notice (the blue dot on the thingy in the system tray), clicked to see the updates,
and I got the behavior described in this thread. Very strange. The Discover updater went no where! Nada. I tried repeatedly.
Frustrated, I rebooted, and it worked.
And as I said, also strange that you guys are talking about 24.04. I recently (September) had this exact same behavior in 22.04.

[Minna]

And as I said, also strange that you guys are talking about 24.04. I recently (September) had this exact same behavior in 22.04.

This is indeed strange. The issue is, I believe, that, every piece of software depends on so many libraries and frameworks, making it almost impossible to find specific errors. It usually works, until it doesn't. Its behaviour is often enough non-deterministic.

If I can't find a solution in the next few days, it will be the end of my long and overall very pleasant Kubuntu journey. Kubi has been a reliable friend for so many years, but this might be the point, where we have to part ways.

[Minna]

Update: The problem mysteriously fixed itself without further intervention on my part.

I have no explanation for this. I suspect a hardware issue, but memory seems fine.