Looks like an old bug with kscreen that could cause two screens to merge together and would be worked around exactly the same way you did. I used to have that whenever a blackout happened, but only with Plasma 5, and often on X11.
What's used under the hood for this is udisks, the same thing used by other file managers to achieve mounting capabilities. It allows you to mount devices without needing to mess with something cryptic and archaic like fstab and doesn't require root.
You can always keep using fstab of course since it works, but in that case you probably also want to use fstab systemd integration.
The KDE auto mount never worked on plasma 6
Please report your issues on https://bugs.kde.org so they can actually get fixed!
Everything. It doesn't accurately describe the issue (animation stutter when using an HDD or during heavy I/O) and it doesn't mention the solution (put the cache folder in tmpfs), plus it obviously follows the traditional sensationalist tone used in clickbait.
The point is to be deliberately vague to bait people into watching it.
It's small enough that we actually don't get many things to moderate either. I don't think I've even done any mod action so far. :D
We're always open to doc contributions. Interested in any particular areas? 🐰
What’s the best or recommended way to test out Plasma 6 RC2?
See also: https://community.kde.org/Plasma/Plasma_6#How_to_use/test_it
I'd be curious to see a blog post in the future mentioning the challenges you might have faced making the dock work on Wayland, and what was needed for that.