I have an issue with some inconsistency regarding to toe/finger tags
1. extra_toes is in plural, the 3 other ones are not
2. extra_digits is redundant and just carried over from Danbooru, and also "extra_fingers" is aliased to this and that's why people use "extra_finger" instead to have a way-around for this.
A BUR has to be made, but not really sure exactly what to do. Do we go with plurals or singular? Should extra_digits go away completely or do we go with implications? Danbooru has fewer_digits as well, but as there are no aliases nor implications linked to it, I don't think this tag is an issue.
My opinion would be:
1) Get rid of extra_digits completely
2) Alias plurals to singulars (so instead of extra_toes we would have extra_toe).