I'm less worried about uglifying URLs, and more about the 404 stuff that a few other people have posted about now. It never occurred to me that there'd be more than an extremely minimal number of sites that would error out when receiving extra query params.

That's a new one for me, I need to make sure I remember it in the future. From what I'm seeing online, it's not even necessarily considered bad practice, so... I dunno anymore.

But agreed, Facebook should back this out.