Problems with upper case umlauts in fragments

[autoantwort]

I have the following markdown code:

[änderungen](#änderungen)  
[Änderungen](#Änderungen)

## Änderungen

Both fragments are valid as you can test here: https://gist.github.com/autoantwort/27be2ae83db76f9227a9f04f6549ba62

But I get

➜  network-documentation git:(master) ✗ lychee -b . test.md --include-fragments
  2/2 ━━━━━━━━━━━━━━━━━━━━ Finished extracting links                                                                                             Issues found in 1 input. Find details below.

[test.md]:
   [ERROR] file:///.../test.md#%C3%A4nderungen

🔍 2 Total (in 0s) ✅ 1 OK 🚫 1 Error

In general fragments are case insensitive.