I mean, it's extremely common - it's hard to have it NOT happen in my experience - but sure, this is just a few seconds and a few moves in on a deal. The left and right stacks are both miscolored, as you can see (just the bottom group of the left, which should be red, and the bottom eleven(!) of the right, which are all legally stacked and moveable and in fact can go with the next two groups above them, so should not be red).
Hmm, interesting! It worked (I think!) previously, but I did some quick changes to it yesterday and probably broke it in ways that I didn't anticipate. The joys of testing a change only too little before assuming it works, apologies.
Not a problem, it's not like I paid for this (though I would have), I just thought you'd really like to know. With some more examination, it seems picking a stack up and putting it right back where it came from almost always screws up the coloring, if that helps nail down the issue.
