It's possible to create a role in a collection for someone who isn't actually a user:
Enter a new email address, random string, or whatever, in the 'user' box in the form at the bottom of the Roles screen.
Press 'Assign role'.
A blank entry gets created in the list of roles above.
At this point, when trying to assign a new role, the drop down list of legitimate users no longer appears. Trying to add another garbage role results in "Error! Could not add role. Please correct any errors below and resubmit."
The blank entry has to be deleted before any more roles can be assigned.
It's possible to create a role in a collection for someone who isn't actually a user:
At this point, when trying to assign a new role, the drop down list of legitimate users no longer appears. Trying to add another garbage role results in "Error! Could not add role. Please correct any errors below and resubmit."
The blank entry has to be deleted before any more roles can be assigned.