Qt Creator replaces legitimate UTF-8 characters (even inside strings) when saving

Problem:

With UTF-8 source code files UTF-8 characters can be used directly in code. Usually they are most likely to be used in string literals. GCC (and i guess also other compilers) have no problem compiling source code with UTF-8 characters.

Unfortunately Qt Creator replaces (at least) the non-breaking space "\u00A0" when not used as an escaped character, but directly as UTF-8 character in the source file.

Steps to reproduce:

Create or edit a source file with a different editor and add a non-breaking space (Unicode 00A0) in a string literal.

Open the file in Qt Creator, change anything and save the file.

Expected behaviour:

The not changed parts of the file are not altered and saved as they were before.

Actual behaviour:
The non-breaking spaces (UTF-8 encoded 0xC2A0) get changed to normal spaces (UTF-8  / ASCII encoded 0x20).

More Information:

The default encoding in my Qt Creator is set to UTF-8. I also tried to disable the "clean whitespace" option of the editor (thinking that might could cause it), but this changed nothing.

Example:

See attached pictures before.png and after.png for a hex editor view of a source file before and after saving it with Qt Creator. The source file in the state of before.png is attached as main.cpp