TYPO3 Core

There are several known problems, most of them related to external link checking, see

• open issues: e.g. #101670 (false positives)
• docs: "Known problems": https://docs.typo3.org/c/typo3/cms-linkvalidator/main/en-us/KnownProblems/Index.html

We propose to deactive the external link checking by default, in order to:

1. have reliable out-of-the-box functionality: functionality which is on by default should work
2. make people more aware of problem (so they can work around it by creating their custom ExternalLinktype or leave external link checking inactive)
3. motivate people to contribute ...

This way people can still use external link checking but there is a visible caveat / disclaimer to raise awareness.