German Umlauts not working in content body

Hello,

I am using a Mac with US Keyboard.

To type German Umlauts, I need to press "+u" first and then the character I want to add the "dots" on.

## Expected behaviour (examples):
+u, then a ---> ä
+u, then U ---> Ü
...

For the non-body string inputs, this works as usual and as expected.
But for the content/body, it does not.

## Actual behaviour on body input:
After pressing +u, the "dots" are showing as expected, but the cursor is placed **before** the "dots". When pressing
a,u,o,... the plain character is displayed without the dots.

It seems that some javascript catches and "handles" the +u, which should be handled by the operating system.