Umlauts in themes are not displayed properly

Good afternoon,
I tried to customize the login theme by adding german translations.
However, I’m facing issues with umlauts not being displayed properly.

When I directly put ä,ö,ü into the properties file only weird signs will be rendered.
When using the html representation ä in the properties file it works sometimes (umlauts are correctly displayed), but not every time (the html representation is displayed).
It seems to be related to a call to kcSanitize around the message. When it is called umlauts are displayed properly.

Do I have to edit all themes to include calls to kcSanitize for all affected messages or is there a simpler way for direct utf-8 support?

Thanks in advance.

Seems more like a bug, wouldn’t expect this to be a problem after so many years into this product.
Check if an issue already exists, otherwise create one.

Thank you for the hint, I found a few similar issues and apparently the way around this is to use the utf-8 representations (\u…).

Thank you for the response, this information could prove to be handy in the future.

If you encode your language files with ISO-8859-1, everything looks fine.