the password cannot contains the same sequences of characters as the old password.
and i have seen this requirement in a service that requires changing it every month for some reasons.
and this is to manage a government digital identity that allows to log it in all governments websites.
with kde 5 i used bismuth, now with kde 6 there is polonium but still a long way to go.
https://github.com/Bismuth-Forge/bismuth https://github.com/zeroxoneafour/polonium