Background Pony #B3A0
Also posting this here as requested in the Fan Site Alternative thread:
I first came across this bug when I was looking for the blood ravens tag in relation to warhammer 40k crossover images.
As you can see here, the tag is logged with 38 pictures, but the search only depicts 37 in total, even with all filters disabled. And if you then look at the tag changes, you see the entry of a pic that was made three days ago, with the picture itself being deleted.
There's a couple of more tags where I noticed a similar behaviour.