Thanks Bob for your reply.
settings > apps > greenshot 1.2.8.12 (2,74 MB @ C/Program Files/Greenshot/unins000.exe) > remove >
Are you sure to completely remove Greenshot and all of its components? > yes >
Uninstall has detected that Greenshot is currently running > OK or Cancel > OK > nothing happens acc to me.

Kind regards, Hermie