[BUG] share maplink in foreign language not working

[wellemut]

Problem

If you use the map in a different language, you see an URL which is not working of you share it or refresh your page. Like
https://www.kartevonmorgen.org/en/m/main?tag=alternative-w%C3%A4hrung

To Reproduce

Steps to reproduce the behavior:

1. Go to https://www.kartevonmorgen.org/m/main?tag=alternative-w%C3%A4hrung
2. Click on the burger menu top right end change your language
3. Copy the URL and paste it in a new tab
4. See error. You can't reach the map

Expected behavior

I would like to see the map in the desired language

Screenshots

Additional context
The problem exists since we use wordpress as landing page