The Q&A box is a form pointed at a pipe

The webinar goes out as an ffmpeg capture of the presenter's display, piped to the audience with ?video. Questions come back on a second pipe path: through /api/v1/pipe/noscript?path=questions&mode=text, a pure HTML form that works in any browser, JavaScript disabled or not.

A student types a question and hits send. On the presenter's second screen, a small loop curls the questions path and prints whatever arrives. Questions trickle in one at a time; the loop drains them as they land.

Outbound video, inbound text, zero platform. The interactive webinar: normally a product with pricing tiers: decomposes into two pipe paths pointed in opposite directions.

The question box is an HTML form that was already there.