What you need: a link that ends up at https://en.wikipedia.org/wiki/Stadskanaal#/maplink/1

What you do: Copy the URL and paste it into VisualEditor's 2017 wikitext mode.

What you get: [[Stadskanaal#/maplink/1]] There is no ovious way to prevent it from changing the URL into an internal link. (Work-around: Copy and paste just half the URL, and then paste in the other half.)

What happens: The link (e.g., after you save the page) takes you to https://en.wikipedia.org/wiki/Stadskanaal#&2Fmaplink&2F1 – which is the wrong/non-existent page.

What's wanted: The link should take you to the correct URL.