Created attachment 116957 [details] shot of activity & error nessage SUMMARY Attempt to delete a key is unsuccessful in software sources. STEPS TO REPRODUCE 1. Muon>Settings>Configure Software Sources>Authentication Tab 2. Highlight a key and click Remove 3. OBSERVED RESULT Attached pop-up window advising to report this as a bug. EXPECTED RESULT SOFTWARE VERSIONS KDE Plasma Version: 5.12.6 KDE Frameworks Version: 5.447.0 Qt Version: 5.9.5 Dolphin: 4:17.12.3-0ubuntu1 ADDITIONAL INFORMATION
could you try doing the same in discover and see if you get a similar error?
Exactly the same result.
Ok so its not muon specific. if you open discover from CLI then try it can you copy the output to here please
scott@scottubuntu:/$ plasma-discover XmbTextListToTextProperty result code -2 invalid kns backend! "/etc/xdg/servicemenu.knsrc" because: "Config group not found! Check your KNS3 installation." invalid kns backend! "/etc/xdg/ksysguard.knsrc" because: "Config group not found! Check your KNS3 installation." no packages for "cockpit.desktop" no packages for "im.riot.webapp" Discarding invalid backend "servicemenu.knsrc" Discarding invalid backend "ksysguard.knsrc" setting currentApplicationBackend PackageKitBackend(0x55a832c63590) THE ABOVE IS JUST OPENING THE APP. FOLLOWING IS NAVIGATING TO SOFTWARE SOURCES XmbTextListToTextProperty result code -2 file:///usr/lib/x86_64-linux-gnu/qt5/qml/QtQuick/Controls.2/org.kde.desktop/ToolBar.qml:37: ReferenceError: is is not defined XmbTextListToTextProperty result code -2 XmbTextListToTextProperty result code -2 org.kde.kdesu: Daemon not safe (not sgid), not using it. XmbTextListToTextProperty result code -2 XmbTextListToTextProperty result code -2 XmbTextListToTextProperty result code -2 Transaction error: "E: http://ppa.launchpad.net/hizo/mkv-extractor-gui/ubuntu bionic InRelease is not (yet) available (Temporary failure resolving 'ppa.launchpad.net')\nE: https://dl.winehq.org/wine-builds/ubuntu bionic InRelease is not (yet) available (Temporary failure resolving 'dl.winehq.org')\nE: http://hk.archive.ubuntu.com/ubuntu bionic InRelease is not (yet) available (Temporary failure resolving 'hk.archive.ubuntu.com')\n" PackageKit::Transaction(0x55a834256d50) qml: message: E: http://ppa.launchpad.net/hizo/mkv-extractor-gui/ubuntu bionic InRelease is not (yet) available (Temporary failure resolving 'ppa.launchpad.net') E: https://dl.winehq.org/wine-builds/ubuntu bionic InRelease is not (yet) available (Temporary failure resolving 'dl.winehq.org') E: http://hk.archive.ubuntu.com/ubuntu bionic InRelease is not (yet) available (Temporary failure resolving 'hk.archive.ubuntu.com') no packages for "cockpit.desktop" no packages for "im.riot.webapp" QObject::~QObject: Timers cannot be stopped from another thread
As a quick workaround please use sudo apt-key rm 0F92290A445B9007 in order to remove the key which is selected in your screenshot. The bug is present in all variants of software-properties. Thank you for reporting! I'm closing this bug in Muon, since the cause is in software-properties. Upstream bug is https://bugs.launchpad.net/ubuntu/+source/software-properties/+bug/1656100