I installed the “Experimental for Arch” Docker Desktop. It was a .pkg.tar.zst file which I had never seen before, but I could install it by double-clicking it. But Docker Desktop does not launch, so I want to delete it I could not find it in Add/Remove software. Double clicking the .pkg.tar.zst again did nothing (expected uninstall GUI). I tried “pacman -Rns file://the path to that file”, but it just said “target not found”.
the last few lines should contain what the name of the package was that you installed
with the name you can then remove it using pacman -Rns ...
… or you could simply look at the packages name …
Looking at the site where you probably got it from
the command to install it is given (as an example - it is missing the “version” part in the file name)