Reminder not sent to pseudo-user assignee()

When targeting a reminder to the pseudouser assignee, the reminder is not sent.

In jira-log it says:

Further information:

• both manually created reminders and reminders created by code have the same problem.

• In Table AO_AFAA51_REMINDER_TARGET the TARGET_TYPE is "USER" and IDENTIFIER is "assignee()". This seems to be correct, as it is the same for manually created reminders.

• Global reminder config has "Add Comment to Issue" = true.

• The comment is indeed added, despite the error: "Erinnerung an "<Remindertext>" an "Bearbeiter" gesendet".

• Reminders are sent correctly to non-pseudo-users.

• Default language of jira-installation is german