URL does not look good

[DanielHabenicht]

Describe the bug
Url is not pretty if a "wrong" URL is given.

To Reproduce
Steps to reproduce the behavior:

1. Go to https://dev.covmap.de/blalalba#/welcome1

Expected behavior
Url should be formatted to index: https://dev.covmap.de/#/welcome1

Screenshots

Desktop (please complete the following information):
Windows Chrome 86