That link goes to Special:ListUsers. These pages are normally opened in-app in an embedded safari window, but with no native elements.

I'm guessing something goes wrong with Special pages in that flow. Digging in now.

Broader problems here - we have some issues in how special pages are handled in all preview situations (long press or from edit preview). Quick audit:

reading article, tap (should get page)

• Normal page - works
• UserTalk page - works
• Special page - works

reading article, long press (should get preview)

• Normal page - works
• UserTalk page - nothing happens
• Special page - nothing happens

edit preview, tap (should get preview)

• Normal page - works
• UserTalk page - previews header, but no body
• Special page - broken, just shows spinner

edit preview, long press (should get preview)

• Normal page - works
• UserTalk page - broken (nothing is previewed)
• Special page - broken (nothing is previewed)

Given that this is a bit larger than initially realized, I'm going to prioritize some other things right now, and come back to this.