TIL the CW counts towards the post length limit
@joepie91 queer.party used to have a patch that would change the post length limit to a much larger value if it had a CW to get around this issue (if you go back far enough in my posts, sometimes I'll have "long post" CWs just to take advantage of that) but it obviously never worked in apps (I once started trying to implement it in Tusky myself, but gave up because I couldn't follow the code than handled length limit checking, especially since I barely know the language (Kotlin iirc)), and Mastodon 4.0 iirc broke it and last I checked maffsie hadn't re-done it
@joepie91 yeah, incredibly annoying