Look at this answer: https://hermeneutics.stackexchange.com/a/1708/864
It contains a single character error, but a quite substantial one - it cites Gen 34:4, when it is clear that the author meant to cite Gen 33:4 instead. So I go click "edit" to correct it, and get this message "Edits must be at least 6 characters; is there something else to improve in this post?"
Honestly, this message is particularly stupid. There is nothing else I want to change in their answer. Why should I have to think up something else to change simply to correct a single character error?