No urls allowed?

Drupal 9 is not supported.

Anti-spam efforts are often discussed in the #support Slack channel. These are typically contributed module solutions.

Why not make the comment plain text only? In Drupal 10.1 you can limit the filter formats on the comment body field

This issue is not exquisitely well-specified, however, I think that’s what they are saying. Link spam is link spam, whether or not the link is rendered into a tag.

Since they’re asking for a validator, in fact, all that is needed is a trivial form alter, and a call to str_contains.

Thanks for feedback much appreciated