Discover not working on Kubuntu 24.04

I think the title says it all … but, the other day my system updated to 24.04 and now plasma-discover no longer works. I’ve tried it using both X and Wayland. From a terminal it just hangs. I even purged plasma-discover and did a fresh install … no luck.

3 Likes

Hello,
This just started happening on my installation as well! Just a few days ago. And some other people as well. Can’t be a coincidence. I suspect there’s something inside something else that is causing this, and circumstances depend whether the system has/is using that something else. This is pure speculation.

Something I did which was suggested to me in the kubuntu support chat, is to run a trace. Console: strace plasma-discover
This actually made the app completely function! But it only works if done via strace command. Otherwise it still just hangs. Make sure first that it’s not still loaded in memory, so clear it from system monitor first.
I am still awaiting further response in the support chat. Might take some time.

2 Likes

Just tried the advice to use strace. Sorry, no joy. Same problem … just lots of text to go with it :slight_smile:

Interesting. Sorry. I am waiting for more responses is both kubuntu support chat and ubuntu channel on Matrix
You can feel free to join them too

Another weird and interesting thing is that, essentially at the same time as this happened with my kubuntu installation Discover, is that I have two laptops with fresh installations of Elementary OS, and the AppCenter app has been having problems on there as well. Just started at around the same time! So weird. Different distro, different app, etc. Although still ubuntu at its core. Maybe something in an update recently broke something under the hood.

I have run “$sudo strace plasma-discover” in the console and this works.
I would rather not run the as a batch file, i have already uninstalled using the purge command and re-installed via sudo apt.

No need for the sudo, hopefully. Try running without it.

What happens with pkcon update this from the cmd line?

pkcon update
Getting updates [=========================]
Finished [=========================]
No packages require updating to newer versions.

And, after this, plasma-discover still hangs with nothing happening from the cmd line.

It does say that no packages require updating to newer versions from the cmd line. You should use simpelscreenrecorder to show the issue. Post the video on YouTube and then post a link. I’m on laptop still running KDE 5 and has 2,745 updates needed from the cmd line.



Just need to see evidence of the Discover hanging. You can also run Ksystemlog to see what’s hanging.

I noticed sometime ago that Discover doesn’t work if there is a root password prompt open for another app.

There is not a request for password from another app.

I certainly could use the screen recorder … but, there is nothing to record.

You(?) asked what happened if I ran “pkcon update” and I showed the results … no suggestions on my screen. No apps launched. Nothing to see.

I just tried from the command line “plasma-discover” and I get exactly nothing. So, I tried again as root and get the following:
bob$ sudo plasma-discover
[sudo] password for bob:
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to ‘/tmp/runtime-root’
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to ‘/tmp/runtime-root’
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to ‘/tmp/runtime-root’
fetch ratings! true
adding empty sources model QStandardItemModel(0x589f59f95860)

Left it for several minutes and finally hit Ctrl-C to terminate the hung process. This time I did have ksystemlog running in a different window, but nothing related is showing up there.

I see references to yast in your example. I’m running ubuntu 24.04 which is a debian system.

Running “sudo apt refresh” tells me that the system is up-to-date.

My current version is:
Operating System: Kubuntu 24.04
KDE Plasma Version: 5.27.11
KDE Frameworks Version: 5.115.0
Qt Version: 5.15.13
Kernel Version: 6.8.0-31-generic (64-bit)
Graphics Platform: X11
Processors: 6 × Intel® Core™ i5-8400 CPU @ 2.80GHz
Memory: 15.5 GiB of RAM
Graphics Processor: NVIDIA GeForce GT 710/PCIe/SSE2

Did you try this to see what’s hanging?

Yes, but I (and I’m not an expert at this) see nothing of worth here. If I start as a user there is nothing at all in ksystemlog (note: I am running ksystemlog as root). But, if I run plasma-discover as root (which we all agree should not be necessary) I get the following entries:
6/2/24 10:30 AM sudo bob : TTY=pts/4 ; PWD=/home/bob ; USER=root ; COMMAND=/usr/bin/plasma-discover
6/2/24 10:30 AM dbus-daemon [system] Activating via systemd: service name=‘org.freedesktop.PackageKit’ unit=‘packagekit.service’ requested by ‘:1.5209’ (uid=0 pid=333211 comm=“plasma-discover” label=“unconfined”)

I’m getting the same issue when running pkcon update:
Getting updates [=========================]
Finished [=========================]
No packages require updating to newer versions.

Is there any progress on a solution for this???

1 Like

UPDATE:

i found this
sudo apt purge plasma-discover-backend-snap
after rebooting it it works again


i have also the issue
discover don’t open on click on the icon or from console

only this helps:
sudo plasma-discover --backends packagekit-backend

then the output shows this:

QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
fetch ratings! false
adding empty sources model QStandardItemModel(0x5de32bf11e90)
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
file:///usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/kirigami.2/BasicListItem.qml:288:18: QML QQuickItem*: Binding loop detected for property "implicitWidth"
no component found for "com.ubuntu.ubuntu"
took really long to fetch PackageKitBackend(0x5de32beab6b0)
file:///usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/kirigami.2/ScrollablePage.qml:200:9: QML MouseArea: Binding loop detected for property "implicitHeight"
file:///usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/kirigami.2/ScrollablePage.qml:200:9: QML MouseArea: Binding loop detected for property "implicitHeight"
file:///usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/kirigami.2/ScrollablePage.qml:200:9: QML MouseArea: Binding loop detected for property "implicitHeight"
file:///usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/kirigami.2/ScrollablePage.qml:200:9: QML MouseArea: Binding loop detected for property "implicitHeight"

i don’t know what to do

2 Likes

Interesting. I certainly get more verbiage using sudo, but still no discover:

sudo plasma-discover --backends packagekit-backend
[sudo] password for bob:
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to ‘/tmp/runtime-root’
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to ‘/tmp/runtime-root’
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to ‘/tmp/runtime-root’
fetch ratings! true
adding empty sources model QStandardItemModel(0x5710d93e0c30)
QQmlApplicationEngine failed to load component
qrc:/qml/DiscoverWindow.qml:167:26: Type Kirigami.NavigationTabBar unavailable
file:///usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/kirigami.2/NavigationTabBar.qml:1:1: Expected a qualified name id
org.kde.plasma.discover: Errors when loading the GUI
KCrash: crashing… crashRecursionCounter = 2
KCrash: Application Name = plasma-discover path = /usr/bin pid = 450822
KCrash: Arguments: /usr/bin/plasma-discover --backends packagekit-backend
KCrash: Attempting to start /usr/lib/x86_64-linux-gnu/libexec/drkonqi
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to ‘/tmp/runtime-root’
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to ‘/tmp/runtime-root’
org.kde.drkonqi: Mapping found despite product information being provided by the application. Consider removing the mapping entry “plasma-discover”
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to ‘/tmp/runtime-root’
file:///usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/kirigami.2/ContextDrawer.qml:135:9: QML ListView: Binding loop detected for property “topMargin”
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to ‘/tmp/runtime-root’
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to ‘/tmp/runtime-root’

[1]+ Stopped sudo plasma-discover --backends packagekit-backend

Without the sudo I get:
bob$ plasma-discover --backends packagekit-backend
fetch ratings! true
adding empty sources model QStandardItemModel(0x631b7ffcf2b0)
QQmlApplicationEngine failed to load component
qrc:/qml/DiscoverWindow.qml:167:26: Type Kirigami.NavigationTabBar unavailable
file:///usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/kirigami.2/NavigationTabBar.qml:1:1: Expected a qualified name id
org.kde.plasma.discover: Errors when loading the GUI
KCrash: crashing… crashRecursionCounter = 2
KCrash: Application Name = plasma-discover path = /usr/bin pid = 451278
KCrash: Arguments: /usr/bin/plasma-discover --backends packagekit-backend
KCrash: Attempting to start /usr/lib/x86_64-linux-gnu/libexec/drkonqi

[2]+ Stopped plasma-discover --backends packagekit-backend

HTH …

$ sudo apt purge plasma-discover-backend-snap
and restart pc has also worked for me.
Thanks

2 Likes

I would not be surprised, at all, if this was a snap issue. But, I did a
sudo apt purge plasma-discover-backend-snap
restarted and … well, no cake and lemonade, but I do get a different error message:
bob$ plasma-discover
fetch ratings! true
adding empty sources model QStandardItemModel(0x62819a05f240)
kf.newstuff.core: The CustomName property is deprecated and will be removed in KF6
kf.newstuff.core: The CustomName property is deprecated and will be removed in KF6
QQmlApplicationEngine failed to load component
qrc:/qml/DiscoverWindow.qml:167:26: Type Kirigami.NavigationTabBar unavailable
file:///usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/kirigami.2/NavigationTabBar.qml:1:1: Expected a qualified name id
org.kde.plasma.discover: Errors when loading the GUI
KCrash: crashing… crashRecursionCounter = 2
KCrash: Application Name = plasma-discover path = /usr/bin pid = 4378
KCrash: Arguments: /usr/bin/plasma-discover
KCrash: Attempting to start /usr/lib/x86_64-linux-gnu/libexec/drkonqi

[1]+ Stopped plasma-discover