UTF-8 characters not recognized in form xml definition file

In my form defintion xml-file I have this configuration:

...

Thsi file is saved as utf-8 file.
I'm rendering the form with this:

The result is:

Ich möchte Lob oder Dank äußern

If I save my form xml definition as ANSI, all characters are displayed correctly.

I think this is wrong. It should output the UTF-8 chars correctly, but not the ANSI chars.