SUMMARY
After a reboot of my system a popup asking for a WiFi password was shown. The password was previously saved in the wallet and I never needed to enter it again until now. When I opened the KWalletManager, I've found out that all my passwords are empty. The entries are still there, but when I click show data, they are all empty. I've tried to manually save the password by entering it to the manager a click save, but I only get error (code -1). The entire wallet seems to be corrupted somehow.

I was rebooting the system after updating it from Plasma 6.5.0 to 6.5.2 in KDE neon User Edition, but I've seen similar report on Manjaro forums regarding older version of Plasma, so the version bump is probably not related. Here is the report: https://forum.manjaro.org/t/kwallet-loses-all-passwords-and-does-not-accept-any-new-ones/179976

STEPS TO REPRODUCE
Can't reproduce it.

OBSERVED RESULT


EXPECTED RESULT


SOFTWARE/OS VERSIONS
Windows: 
macOS: 
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: KDE neon User Edition
KDE Plasma Version: 6.5.2
KDE Frameworks Version: 6.19
Qt Version: 6.9.3

ADDITIONAL INFORMATION
I never changed any setting regarding the wallet, it is the default setup from KDE neon. I've only had 4 passwords for Network Manager and 2 passwords for KRDC stored. They were all stored a long time ago, so no writes to the wallet have been made during the last boot.

I'm sure that I was connecting to a RDP server via KRDC just before the reboot and my password for the KRDC was read correctly from the wallet. The password for my WiFi after the reboot was not, so it must have got corrupted during the reboot.

The kdewallet.kwl file is present and it is not empty (1240 bytes), but its modification time and even birth time show, that it was re-created just in the time of the popup for the WiFi password.