Views RSS feeds have validation issues

+++ b/core/modules/views/src/Plugin/views/style/Rss.php
@@ -88,7 +88,19 @@ public function buildOptionsForm(&$form, FormStateInterface $form_state) {
+    $url = $this->view->getUrl()->setAbsolute()->toString();

Are we sure this is always going to return the correct path? Is the display always set to the RSS display when we reach this point or can we get a page display or a fatal error here?

Also, I agree with #36, is this the best way to fix this? This could lead to the same element being there multiple times. It might be the best way, but having some validation for this route over changing the template would be good.

Still errors of unknown namespaces...

The IS is still talking about D7 and contrib View, where it looks like this has actually been addressed, so could somebody update the IS to make it more current? I'm assuming this is still an issue

Aside from the issue summary update, there is a fix here for the cdata that is out in 11.0 and 10.4 🐛 Use CDATA in XML RSS Feeds Fixed .

The core rss feed should be generated on that version and run through a validator to identify any remaining issues.

Have tested on 11.x and it still producing the same recommendation. Updated the issue summary steps to remove reference to drupal 7 and use terminology in the current views UI - also tweaked to title to clarify this is a recommendation not an error.

Moved the existing patch to an MR.

Tested again and Len's comment is #42 is correct - this patch causes an error when following the steps to reproduce. Once you add the new view and before saving it the preview will through an exception as we are trying to get a route for a view that does not exist.

Once the view is saved the validation recommendation is resolved - leaving as "Needs work" as the approach to resolve the issue does not have consensus.