If a wither skeleton is wearing armor, that armor will be invisible. The armor will still drop, break and give it's benefits to the wither skeleton but is invisible. While it doesn't affect most players, this is a problem for map makers who like giving mobs different looks/loot drops.
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Comments 2
Same for evokers, vexes, villagers, and witches.
Thank you for your report!
We're actually already tracking this issue at MCPE-44488, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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