Operating System: Arch Linux
KDE Plasma Version: 5.23.4
KDE Frameworks Version: 5.88.0
Qt Version: 5.15.2
Kernel Version: 5.15.7-xanmod1-tt-1 (64-bit)
Graphics Platform: X11
Processors: 64 × AMD Ryzen Threadripper 3970X 32-Core Processor
Memory: 62.7 GiB of RAM

plasma-discover 5.23.4

$ plasma-discover --listbackends
Available backends:
* flatpak-backend
* fwupd-backend
* kns-backend
* packagekit-backend

$ plasma-discover-update
** (process:185711): WARNING **: 12:20:59.293: Not changing AppStream cache location: No longer supported.
QDir::mkpath: Empty or null file name

** (process:185711): WARNING **: 12:20:59.293: Not changing AppStream cache location: No longer supported.
QDir::mkpath: Empty or null file name
adding empty sources model QStandardItemModel(0x55ea5b4c1040)

(process:185711): Fwupd-CRITICAL **: 12:20:59.515: fwupd_client_download_bytes_async: assertion 'url != NULL' failed
ready 0
steady 0
No updates available, exiting

$ plasma-discover --mode Update
Icon theme "ubuntu-mono-dark" not found.
Icon theme "Mint-X" not found.
kf.sonnet.core: Sonnet: Unable to load plugin "/usr/lib/qt/plugins/kf5/sonnet/sonnet_aspell.so" Error: "No se puede cargar la biblioteca /usr/lib/qt/plugins/kf5/sonnet/sonnet_aspell.so: (libaspell.so.15: cannot open shared object file: No such file or directory)"
kf.sonnet.core: Sonnet: Unable to load plugin "/usr/lib/qt/plugins/kf5/sonnet/sonnet_hspell.so" Error: "No se puede cargar la biblioteca /usr/lib/qt/plugins/kf5/sonnet/sonnet_hspell.so: (libhspell.so.0: cannot open shared object file: No such file or directory)"
kf.sonnet.core: Sonnet: Unable to load plugin "/usr/lib/qt/plugins/kf5/sonnet/sonnet_voikko.so" Error: "No se puede cargar la biblioteca /usr/lib/qt/plugins/kf5/sonnet/sonnet_voikko.so: (libvoikko.so.1: cannot open shared object file: No such file or directory)"
kf.sonnet.core: Sonnet: Unable to load plugin "/usr/lib/qt/plugins/kf5/sonnet/sonnet_aspell.so" Error: "No se puede cargar la biblioteca /usr/lib/qt/plugins/kf5/sonnet/sonnet_aspell.so: (libaspell.so.15: cannot open shared object file: No such file or directory)"
kf.sonnet.core: Sonnet: Unable to load plugin "/usr/lib/qt/plugins/kf5/sonnet/sonnet_hspell.so" Error: "No se puede cargar la biblioteca /usr/lib/qt/plugins/kf5/sonnet/sonnet_hspell.so: (libhspell.so.0: cannot open shared object file: No such file or directory)"
kf.sonnet.core: Sonnet: Unable to load plugin "/usr/lib/qt/plugins/kf5/sonnet/sonnet_voikko.so" Error: "No se puede cargar la biblioteca /usr/lib/qt/plugins/kf5/sonnet/sonnet_voikko.so: (libvoikko.so.1: cannot open shared object file: No such file or directory)"

** (process:185813): WARNING **: 12:21:34.470: Not changing AppStream cache location: No longer supported.
QDir::mkpath: Empty or null file name

** (process:185813): WARNING **: 12:21:34.470: Not changing AppStream cache location: No longer supported.
QDir::mkpath: Empty or null file name
adding empty sources model QStandardItemModel(0x55c05becf740)
org.kde.plasma.libdiscover: Couldn't find a category for "fwupd-backend"
file:///usr/lib/qt/qml/org/kde/kirigami.2/private/PrivateActionToolButton.qml:74:5: QML Binding: Binding loop detected for property "value"

(process:185813): Fwupd-CRITICAL **: 12:21:34.734: fwupd_client_download_bytes_async: assertion 'url != NULL' failed
file:///usr/lib/qt/qml/org/kde/kirigami.2/private/globaltoolbar/ToolBarPageHeader.qml:83:13: QML Binding: Binding loop detected for property "value"
file:///usr/lib/qt/qml/org/kde/kirigami.2/private/globaltoolbar/ToolBarPageHeader.qml:88:13: QML Binding: Binding loop detected for property "value"

(process:185813): Fwupd-CRITICAL **: 12:21:41.264: fwupd_client_download_bytes_async: assertion 'url != NULL' failed


There are updates to both 2 KDE themes (installed from Plasma) and 113 Arch packages.

"plasma-discover-update" doesn't find any update.
"plasma-discover --mode Update" only shows the Plasma themes updates (Screenshot_20211211_122239.png).