Some author pages empty for some logged in users

I first posted about this over on Wordpress.org: https://wordpress.org/support/topic/some-author-pages-empty-for-some-logged-in-users/

Now there is another user commenting with the same problem, so I thought I'd post the issue here.

Some authors display as having no posts, but only to logged in users.

For example, while logged in, this page will display “No posts found.” to me:
https://example.com/wp-admin/edit.php?author_name=randomauthor1
And if that one doesn’t work for me, then neither does this one:
https://example.com/author/randomauthor1/

But randomauthor2 will work just fine.

However, oddly enough, logging in as a different user will change which authors don’t work and which ones do. In fact, we’ve got more than 20 authors, and all but one of the author pages work for me. But another user on the site reports that 5 of them fail to load for him.

And if you’re not logged in, the public author pages seem to work just fine (although that’s hard for me to prove with 100% certainty.)

Start by reproducing the issue at the provided wp-admin author URL and public author URL while logged in as different users, then compare those results with the logged-out behavior. Done means affected authors consistently display their posts for logged-in users without breaking the working author pages.

Written by the indexing model from the issue text.