When you're in the inventory, the armor sometimes is not displayed on the player model. This also sometimes happens on the little player image that appears in the corner while sprinting or swimming.
Comments 2
Cleaning up old tickets: This ticket had been set to 'Awaiting Response', but has not received a response from the reporter (~3 months+) so is being closed as Incomplete. If you feel this is still a valid issue then please comment, or create a new ticket following the Issue Guidelines which includes steps to reproduce the problem.
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Had you "minimised" (so returned to the Dashboard or similar) prior to it happening?