Cannot load Tiff file on Windows from directory with german special letters

[cdhf]

On Windows 10 with Julia 1.5 and ImageMagick.jl v1.1.6. I cannot load Tiff files, if the path to the file contains german "Umlaute" (ä, ü, ö).

The error message is this:

ERROR: UnableToOpenBlob `c:\tmp\Übung\test.tif': No such file or directory @ error/blob.c/OpenBlob/2873

This works:
load(joinpath("c:\", "tmp", "Uebung", "test.tif")) or load("c\tmp\Uebung\test.tif")

This does not
load(joinpath("c:\", "tmp", "Übung", "test.tif")) or load("c\tmp\Übung\test.tif")

The file is the same in both cases. It works on Linux.