domains with umlauts are not functional in post

[foss-]

Bug Description

What it says on the tin. Previously reported as #2487 and fixed in #6835 back in march 2019.

Steps to Reproduce

1. create a post just says https://tästdomain.com
2. in the resulting post click on the link

Actual Result:

Nothing, no new tab or domain opens.
Umlaut is changed to [url=https://t%C3%A4stdomain.com]https://tästdomain.com[/url]

Expected Result:

Link should open

Version: This is Friendica, version 2024.06-dev that is running at the web location https://squeet.me. The database version is 1560/1560, the post update version is 1550/1550.

[MrPetovan]

The produced HTML is

<a href="https://xn--tstdomain-v2a.com" target="_blank" rel="noopener noreferrer">tästdomain.com</a>

Where the href correctly sends to tästdomain.com, but the link indeed isn't clickable in the preview post. 🤷‍♂️