Why does this have "- Freeform" at the end? and other questions about AO3 tag suffixes

Have you ever tagged something only for it to get a suffix like Character, Relationship or Freeform stuck on the end when you hit save? Do you think it's ugly and want it to go away, but don't know how? You probably can't, unfortunately, but there are a few situations where you can.

A tag suffix is a hyphen followed by the name of a tag category. Tags are either Fandom, Character, Relationship or Freeform tags. The reason that a suffix gets put on a tag is that the wrangulator (the part of AO3's backend that deals with tags) can't have tags with the same name, even if they're in different categories. As a solution, it puts the category at the end of tags that have first been tagged in some other category. For example: let's say that someone tags Evil Mark Donk in the characters field because that's where they want it to appear on their work (which is a perfectly valid choice to make!). Then someone else comes along and tries to tag Evil Mark Donk in the additional tags/freeforms field. (That field is shown as "additional tags" on the posting form, but the wrangulator and tag wranglers call it the "freeforms" because that's what it was originally called.) When the second person hits save, it will appear as Evil Mark Donk - Freeform on their fic. This will also happen if someone tags Evil Mark Donk in the relationships field, but there it would appear as Evil Mark Donk - Relationship. It's ugly and it's annoying, but the wrangulator is trying its best.

So how do you get rid of it? Sometimes it turns up because you've accidentally put your tags in the wrong field. Maybe you wrote a fic where you tagged Evil Mark Donk in the additional tags field, and no one else had tagged for it before you, which means it doesn't have a suffix and everything's right! But then you write a second fic, forgot to select the "additional tags" field when posting and now suddenly you've got Evil Mark Donk - Character on your fic. If that's the case, all you have to do is move it. But what if the first person to tag it wasn't you, and they put it in the character field, so you're stuck with Evil Mark Donk - Freeform? You can choose a different phrasing for the tag that wasn't initially tagged in a different field, e.g. Evil!Mark Donk or Mark Donk is Evil.

You may also have the problem that on the first use of a particular tag, you accidentally put it in a field you don't want it to be in, and now even when you put it in the right one, it still comes up as Evil Mark Donk - Freeform! The wrangulator has betrayed you, and you will be stuck with the ugly suffix forever! Not so, my friend. The problem is that even though you deleted the character tag Evil Mark Donk, it's still floating around in the wrangulator, which hasn't noticed that you deleted it. What you have to do is wait for 24 hours (give it a few for leeway) and a part of the wrangulator called "the rake" will delete it. After it's been raked, you can go forth and post it in the additional tags field, and no suffix will appear!

Unfortunately, most of the time it's going to be that someone else tagged it in a category you don't want to tag it first, and you can't change it without changing the phrasing of your tag. Sorry!

Sometimes, taggers will add their own suffixes, and tag wranglers are extremely curious about why. If you've done this, or something similar like put (freeform) in brackets after a tag, please let us know why! What does freeform mean to you? You are of course free to put suffixes on manually if you want -- it's a valid way to tag! We are just fascinated by this practice and don't really understand it. Please enlighten us!

For more information about tags, I've written some other explanations about how tags work, such as how to tell what type of tag something is and tag capitalisation.