Board Thread:Support Requests - Getting Technical/@comment-26601886-20151205171143/@comment-4731443-20151205195254

You're right. Looking at other related messages, it would be the header text that appears just above the thumbnails of the exhibition as shown in the Help page you linked to. Apparently it picks a different message based on content (or namespace?).

category-exhibition-blogs-header: Blog posts category-exhibition-media-header: Media in category "$1" category-exhibition-page-header: Pages in category "$1" category-exhibition-subcategories-header: Subcategories