Description of the need When anonymous users are set to post comments, then additional configuration settings for anonymous commenting appear on the content type settings. Two of them allow anonymous authors to leave links to their homepages.
In most cases the field is abused by spammers who put ad links in that field. Despite it is possible to easily hide or remove the field using template overrides, I believe this field should be properly changed in core.
Proposed solution I would completely remove the field, however considering those rare websites which need visitors to leave their homepage links, we could make this configurable just in the same way as the comment titles are allowed or not like shown on the screenshot for proposed change.

Recent comments
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