I've found two major bugs.
1. Inventory bug. I've heard other people talking about this, but I think I know what the problem is. The inventory grows as you collect more items, the problem is, the growth seems to be based on exactly how many items you have. So if you have 20 different items, you'll have twenty slots. The problem with this is that if you get rid of a stack completely that isn't all the way to the right, your inventory will shrink down anyway and you won't be able to use or see your rightmost item anymore. Get rid of a few slots at once, and you can lose several valuable items and stacks of items. Whats worse is that if you collect the same item that got lost in your inventory, it wont stack properly, meaning that once you fill your inventory up again, you will have two different stacks of the same item, which causes its own issues. This can make it seem like your items are disappearing at random. You could fix this by either adding an exception so that you will always be able to see up to the slot that has an item in it, or making items automatically move to the left. Or just not hiding all the extra inventory slots at all, and have them and their empty circles visible at all times.
2. Save bug. The game can save into an unwinnable state. I had to restart because my first game autosaved on a game over screen, so every time I load it, I instantly get a game over. The game is effectively permadeath.