1. Go to a talk page with the wikitext 2017 editor.
2. Want to add a link (or ctrl + k) in a topic to explain something {F31818165}
3. Copy the url of link
4. Normally if the page is a wiki url it converts automatically. (e.g. https://fr.wikipedia.org/wiki/Canada) -> [[Canada]]) . And a external url (e.g https://www.google.com/ move automaticaly to External link tab.
5. In a discussion page you may need to put a link to a diff or history wiki page.
5. The editor converts the link from the history or diff to a wiki link.
(https://fr.wikipedia.org/w/index.php?title=Canada&action=history) or a diff (https://fr.wikipedia.org/w/index.php?diff=170545955&oldid=170521399&title=Canada&diffmode=source) it always converts to an internal link -> [[Canada]].
6. You have to click manually on the external link.
When the url contains &action or &diff, it should then consider the link as external and not convert it.