Manjaro KDE just upgraded to plasma 5.21.

A friend of mine that uses Manjaro KDE told me that after today’s update, when he entered his password, the desktop was no longer initializing.

So I updated one of my computers myself, one that uses auto-login, and I got this:

https://i.imgur.com/ctKf80a.jpg

When starting plasmashell from the tty I got:

Could not load the Qt platform plugin “xcb” in “” even though it was found.

The journal shows a problem with libc:

https://i.imgur.com/vry92iW.jpg

And the sddm.service shows:

Auth: sddm-helper exited with 1

I have fixed it by removing kwin-lowlatency, and installing kwin.

They are telling me that the official kwin now has the benefits of lowlatency too.