Mobs can drop chainmail armor (and probably others) with 0 durability on them. This is a simple issue, and the easiest solution is just putting the rng minimum to 1. Attached is a screenshot of a 0 durability helmet I found.
MC-252367
0 durability items possible
Resolved
Duplicate
0
HyperCodec
(Unassigned)
Unconfirmed
(Unassigned)
1.18.2, 1.19 Pre-release 4
Retrieved
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We're tracking this issue as MC-136374, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as Won't Fix, which means this is considered a bug but won't be fixed. The description of that ticket or the comments might explain the rationale. Please do not leave a comment on the linked ticket.
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