In a draft submission, URL values in WebformLink or in Url elements might be invalid; which might break code which assume that a link element always contain valid URL object at the #url key. We discovered this issue on an environment having Menu Link Destination also installed. If there is a draft submission with invalid Url or WebformLink element, and the user visits the route of the result list, then MenuLinkDestination::preRenderLink() causes a fatal.
First we though that this is a bug in Menu Link Destination module. But the docblock of the Link render element declares that #url must be a \Drupal\Core\Url object. By using PathValidatorInterface::getUrlIfValid(), Webform tries to ensure that it only adds valid Url object to the link renderable, but it does not handle the case when the method returns FALSE.
If the Url does not validate, then pass a Url object to the #url of the link renderable array.
Satisfying the requirements of the Link render element seems to be obvious; so I don't think we need any tests coverage in this case.
Minor: Urls and WebformLink elements with invalid Url object are rendered on the Webform submission list (revealing the title of the link, if any).
Nothing.
Nothing.
Needs review
6.2
Code