For some reason backslashes get deleted whenever you preview, edit or save a comment. If you write "\", then hit preview, you can see the "\" is gone in the preview. You gotta go with double-backslash "\\" in which case only the first is deleted. Same for if you post a message and then delete it.
It
really messes with
too, and double-backlashes have to be written four times \\\\. (<- this one I wrote eight times)