Items manually placed in crafting table grid, if not crafted, will remain in crafting table inventory,cand do not sutomatically return to player inventory. Re-opening crafting table gui displays left items, which can be manually removed from grid to return them to player inventory.
Could not reproduce in Windows 10 1.16.100.56 Beta. I place a stack of oak logs in the crafting table and crafted planks once, giving me 4 planks and leaving 63 logs. I placed the planks in my inventory and closed the UI without removing the logs. The logs moved back to my inventory.
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