Not sure if bug was reported previously, and it's more of a nuisance, but I was just harvesting some barley and once the bucket had 300 seeds in it it started dumping it all in inventory. Did it twice, and not being the farmer I just assumed that's how much a bucket could hold, but then sampled the barrel's contents to check the mixed quality and noticed it can indeed hold 1000 seeds.
Also, this happened with the barley only, as the flax i harvested was fine.