Created attachment 103922 [details]
[gif anim of the bug]

Hi,
Krita follows on my system the value of my locales[1], this is nice.
   eg. 0,42 for fr_FR.UTF-8 instead of 0.42 for fr_FR.UTF-8 
   Note the difference, comma instead of dot :-)

The problem/bug is that I can't edit the widget using a decimal written with comma. Krita displays them this way, but I can't edit them this way ( right click on a widget to edit value manually ). Only entering a number with a dot will work. 

I attach to this bug report a quick gif animation to illustrate the bug in action.

[1] ref for my locales:
LANG=en_US.UTF-8
LANGUAGE=
LC_CTYPE="en_US.UTF-8"
LC_NUMERIC=fr_FR.UTF-8
LC_TIME="en_US.UTF-8"
LC_COLLATE="en_US.UTF-8"
LC_MONETARY=fr_FR.UTF-8
LC_MESSAGES="en_US.UTF-8"
LC_PAPER=fr_FR.UTF-8
LC_NAME=fr_FR.UTF-8
LC_ADDRESS=fr_FR.UTF-8
LC_TELEPHONE=fr_FR.UTF-8
LC_MEASUREMENT=fr_FR.UTF-8
LC_IDENTIFICATION=fr_FR.UTF-8
LC_ALL=