The Bug:
Placing a block with your offhand resets your mainhand weapon cooldown
How to Reproduce:
Place a block with your offhand and then quickly attack an entity with a sword
Observed Behavior:
The weapon does a weak attack, not producing a sweep hit and doing less damage
Expected Behavior:
Placing blocks in offhand would not affect the cooldown of your mainhand weapon
Since this bug doesn't happen when using your offhand to eat food or shoot a bow, I'm assuming it has to do with the swinging animation that happens when you place a block (the same animation that plays when you attack).
In the attached video you can see the fully charged sword attacks producing a sweeping effect, but after placing a block the sword isn't charged, so it does a weak attack instead.
[media]
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We're tracking this issue in MC-118740, so this ticket is being resolved and linked as a duplicate.
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