The duplication part relates to MC-205454
Creating a crafting recipe, then clicking one item out with a bundle, leaving one slot empty, will leave the recipe still there. Once it is clicked, the items in the crafting grid will duplicate and when repeated, the items can go beyond a stack of 64.
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I think this should be considered a duplicate of MC-205454 unless in can be recreated without that bug.
May also relate to MC-114462
I'd consider this to be the same issue as MC-205454. If the issue persists after that one has been fixed, please create a new bug report.
Can confirm.