The tag alias #66170 ft -> invalid_tag has been approved.

Reason: Feet? Feat? Female To? This is ambiguous and useless, I considered if it should be ft_(disambiguation) but invalid_tag may be better for this one, it's hard to guess what it could even mean from the limited amount of characters in the tag name.

EDIT: The tag alias ft -> invalid_tag (forum #389519) has been approved by @slyroon.

might be a truncated female_to_<something> as well, but it's kind of impossible to tell what the tag was meant for in any of the posts containing it.
a few of the tags are lacking gender tags, so maybe?

EDIT: the only one I can really determine the reason of was this one: post #681179 who has the tags ft and lt at the FA source, reading the description it's because the character featured has the title "Ft. Lt." which I think is an abbreviation of "Flight Lieutenant", although, that's normally "Flt Lt"... also, I don't know why an air force pilot is operating artillery.

The tag alias ft -> invalid_tag (forum #389519) has been approved by @slyroon.