I ran along a trail and found a small stone. The pop-up showed it as 8/8 (i.e., 8 stones) instead of 1/8 as usual. After picking it up it was also displayed as 8/8 in my inventory. I tried to split the stack of stones using RMB, but couldn't. I could move it around the inventory slots and it would still show 8/8. For all practical purposes it behaved as a single stone even though the counter showed 8.

When I rejoined after a crash, the stone was displayed correctly as 1/8 in my inventory.

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