I have a similar problem.
As the Superadmin of a multisite-Setup, I can select the main user of any of the blogs. But as the Blog owner, who is just an Administrator, not a Super-Administrator, I can not choose any username, the corresponding drop-down remains empty, the three dots “….” at the right of the drop-down keep moving, as if it was trying to load the user list but could not, or it was taking forever to load.
I just figured out how to solve my problem. Even though there’s a drop down menu, just ignore it and type your user name or ID into the empty box. When you’ve added your user name it should find it and then you can highlight and save it.
Interesting, richards1052, but on my screen, it is a drop-down, not an entry-field, so I can’t type anything. :-O
Mine has a drop down menu as well. But I just put my cursor in the field & started typing my name and my account displayed.
Interesting. I can do that if I log in with my superuser account. If I only log in with a blog administrator account (I have a multisite install, remember?) then I can not enter anything there, the drop-down box seems to hang in its initialization code.
This thread has been marked as resolved as the original poster confirmed the issue as resolved on their site.
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