What if the user has JavaScript disabled or has a hardened browser that disables WebWorker / WASM ????

[ForestJohnson]

Jeremys phone could not do the captcha. What do we do about that ? For capsul, I made an alternative option where the user would be prompted to send us an email to verify that they are a real person. That seemed to work for capsul for now. It should be integrated into this service as an optional feature.

See https://git.cyberia.club/cyberia/smtpd-delivery-monitor/src/branch/main/imap_get_messages.go
and https://git.cyberia.club/cyberia/smtpd-delivery-monitor/src/branch/main/main.go#L354

[strangersdangers]

You can also do something like MCaptcha did as well.