Haven’t test it on earlier versions, but using Unity 2019.2.0f1 and Unity.Collections preview-0.1.1, using the ParallelWriter version will cause leak when trying to Dequeue. You can replicate this in the main thread or in a job. All you need is NativeQueue.ParallelWriter version executing Enqueue.
I have submitted a repo with the case number 1175386.
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