RESOLVED: Accept the new text for grid and multi-col changing the floor to a required amount. The new text is: "For the purpose of finding the number of auto-repeated tracks, the UA must floor the track size to a UA-specified value to avoid division by zero. It is suggested that this floor be ''1px'' or less."

https://lists.w3.org/Archives/Public/www-style/2016Jan/0031.html