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!
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.
Please report your issues on https://bugs.kde.org so they can actually get fixed!