Multi-monitor support
It seems to create a 1920x1080 window on my main monitor with the content of my left screen (+a bit more since my left screen has a smaller resolution) when I start color picking mode. The color preview thing that should follow the mouse pointer is extremly set off in that case as well.
I use Xfce4/xfwm on Arch Linux, there are no problems when I disable one of the monitors.
Unfortunately i don't have a second monitor that would allow me to test multi monitor support yet. I'll try to add multi monitor support in the next version.
You could try to use the screen of your phone as a second monitor e.g. by using evdi: https://unix.stackexchange.com/questions/585069/unable-to-add-a-virtual-display-to-xorg This should work no matter the vendor of the graphics card (other ways only work with Intel or Nvidia).
Great, didn't know that exists. I'll try that.
Multi-monitor would be great. This is a great tool, and the only color picker I have found that allows for directly launching a picker with magnifier + color info. But no multi-monitor support really limits its usability.