Special:Badtitle/NS90:Template talk:Tropestub/What's happening on this page?

When I visit Template:Tropestub while logged in, I get anon's view (Create account | Log in) and then my own logged-in sidebar (Damian Yerrick (0) | Talk | Sandbox | Preferences etc.) slides in to replace it. When I click "View source" on anon's view, I get taken to an edit form, but when I try to preview or submit from this edit form, it takes me back to anon's view where my logged-in sidebar once again slides in.