Comment # 7 on bug 1184058 from Felix Miata

Another test box, gx780, is not reproducing this (as root) in TW20210729/Plasma
5.22.4. So I went back to gx151, upgraded it to 20210729, and found the problem
remains. I also noticed the digital clock is missing from the panel. Initial
attempt to add the digital clock failed to respond, then the 2 minutes were up
and the session exited. I then logged out, removed ~/.cache/*, and logged in,
which didn't help, so I logged out again, removed ~/.cache/* again, removed all
of Plasma's files in ~/.local/share/ and ~/.config/ (except a few, such as
fonts and Konsole-related), spent 10 minutes in systemsettings5, and everything
is now fine, except for the invisible clock. Next I upgraded the comment #0
host hpg33 to 20210729 and found no improvement. I logged out on it, deleted
the same .local, .cache and .config files as on gx151, spent 10 minutes in
systemsettings5, and everything is now apparently fine on it too, including a
visible clock. So -> WORKSFORME