There is this site http://game-icons.net/ that offers huge number of open source icons. That is 1345 SVG files to this day. I would love to use them with a web project I am working on right now. The logical step is to transform them into an icon font. Normally, I would just upload them to https://icomoon.io/app/#/select/font and voila ... but!
The icons are inverse, white symbols on a black rectangle. I can invert colors in Illustrator, but some of the icons have overlaping shapes and this breaks them when icomoon tries to make them Black-transparent.
Example: http://game-icons.net/lorc/originals/archery-target.html The circles are white, not transparent.
How to flatten a Black-White SVG file with overlaping shapes into an icomoon friendly Black-transparent SVG?
My wish is to make the font open source as well and send it back to the site admins for everybody to enjoy.