It seems that the saving of the fill layers writes out the files in the current locale thanks to QDomElement. So for me the color of the fill layer is saved as:
The behaviour of QString has been changed in this regard. In 4.8 it first tried the current locale and then C locale. In 5.x only the C locale is used to convert to double. The attached patch fixes the problem by using available functions to convert the doubles.
559255d Fix loading of filllayers
.../lcms2/colorspaces/rgb_u16/RgbU16ColorSpace.cpp | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
Upstream: quickgit.kde.org