Hello! First of all, I want to start with saying that I'm loving the design of the new update so far! I like the improvements to some of the tasks.
While I was busy testing out some of the new features (primarily, the new coloring function for tasks), I did notice that the fill ends up matching the color of the box, thus making them completely invisible when deselected. Somehow, this works perfectly fine with checkboxes.
Here is an image describing the situation:
I also want to state that it also looks fine with the fill progression with timers, too.