Hi Heikki, as you pointed out, this is resolved in the new Kickoff menu. If there were a patch, we could apply it and resolve the issue. But it seems the only solution is to use the new Kickoff menu. Then I'm afraid we won't be able to fix it for the Plasma version in Bullseye.
However, as soon as Bullseye is released, we plan to push the newest Plasma version from experimental to unstable and then it will be available in testing soon after, if you want to install it from there. If you have nothing further to add, I'll close the bug. -- Med vänliga hälsningar Patrick Franz