I am using plasmashell –version plasmashell 6.3.6
I have navigated to System Settings > Window Management > KWin Scripts.
Bug 1]
On the right hand side of the screen, there are a list of pre-installed scripts which are not deletable (Desktop Change OSD, Minimize All, Synchronize Skip Switcher with Taskbar, Video Wall).
[Critical] Bug 2]
I proceded to click “Get New…” in the top right corner and installed software called “Krohnkite”. It appeared in the KWin Scripts section. I have decided I do not want to use this software, and now it cannot be removed from the machine – the trash can is greyed out.