Banner pattern images getting replaced

I couldn't get this to happen again so I don't know what exactly did happen but, I was messing around with the patterns, and then the pics in the pattern selection thing started changing into the ones in the preview. Whenever I clicked on a new pattern the preview replaced the next one on the list. I think the pics explain it better, to be honest?
(And I don't know if this is an issue in the other snapshots, since I guess I don't know if it's an issue at all haha oops)