now, where issue #2021 was solved and the loooong key can be displayed I decided
to delete it. I selected that key and tried Keys -> "Delete Keys". I clicked at
"Yes" at the info popup window with that key info, but got then:
The GPGME library returned an unexpected
error at gpakeydeleteop.c:208. The error was:
No public key
This is either an installation problem or a bug in GPA.
GPA will now try to recover from this error.