This should be fixed in the latest package.
in fact in the directory only the dir data is left and it is empty but root:root is the owner
after rmdir /home/yellowtent/appsdata/f266ef68-b01b-4a9e-954e-b8bc68010672/data
the uninstallation went well 😉
@nebulon Thanks, this was the reason for my problem. After I uncheck "mounted filesystem" Cloudron was updated to 5.4.1