Roan Kattouw wrote:
Brion Vibber schreef:
A second-simplest might be to provide alternatives in fixed formats -- eg, image URL or text fragment. Consider also futureproofing for audio alternatives.
That's what I was thinking. Audio fragments could also use the URL field.
If so you should probably provide a type field (image/png, audio/wav, etc). Otherwise the intermediary app may not be able to guess how to present the challenge without downloading it separately first (possibly requiring a second download for the presentation).
-- brion vibber (brion @ wikimedia.org)