OK, that was odd. We're travelling for the holiday, so I figured I'd get ssh running on port 443 in case I ended up behind a dumb middlebox.

(HTTPS is client-first and SSH is either-first, so they can share)

Went to patch my local copy of Warp, found that 2019 me had already done so ... but apparently *also* hit an even more annoying middlebox that would filter any stream starting with 'SSH-', regardless of port?!