[icedchai]

In these situations, store your IPv6 prefixes in a config. This doesn’t sound like a hard problem to solve.

[the_mitsuhiko]

Which is a manual process and because it is one it leaves many systems unprotected.

[icedchai]

Systems that crawl user provided URLs are in the minority. For most systems it is irrelevant.

[the_mitsuhiko]

I strongly disagree. Almost every single system has webhooks which by definition are user supplied URLs.