People seem to misuse (see original discussion: forum #10858) signed and watermark for a very long time, so I revised watermark wiki page to make it more clear, and started to clean them up.

Feel free to help remove these tags if they don't meet the criteria mentioned in watermark wiki page.

I'm also planning to merge these two later, as there is no point to keep two very similar tags. But this up to debate.

Or alternatively, we can keep them for different purposes: watermark for 3rd party ones (and should be avoided in general), and another tag (not sure signed would be the best word to use) for official, but ugly and intrusive ones like post #419511. Still, posts like post #427889 should not be tagged at all, these are "fault" type tags for a reason.

I bet there's some confusion between in-universe autographs imposed on images (see aikatsu! artwork for examples) and cases of artist adding his trademark somewhere.

edit: And also some authors sign their art with shapes like handwritten autographs, while others do it using more or less common typefaces. Adds to counter-intuitiveness of tag names.

autographed is for autographs that have some aesthetic values (not necessarily need to be a handwritten one, but at least trying to resemble).

Temporarily changed all inappropriate watermark to official_watermark, and at this point I'm not sure if we're going to keep it.

Going to clean up signed later.

Also, I updated autographed, so please make sure to use it properly as well.