using a spoiler tag, center tag, or strikethrough text in any sort of way seems to create this error: "Your message contains too few characters. :: Error #3 (0)"
i can't edit this post at all because there's spoiler tags in it nor can i make a post that has these tags in it. previewing or submitting the post just outright removes everything in the text box and produces the error in question.
it should be noted that i'm also not using a WYSIWYG editor of any kind so there's no hidden unicode characters lurking in my posts that would be causing this issue (my post size isn't being bloated by hidden characters for example). it's specifically these listed tags every time. fwiw, i've tried to edit the post i've linked as well as separating my edit into a new post with the same formatting 9+ times but failed each time because of the spoiler tags.