How to reproduce:
1. Open attached project "UnityRequests.zip" and scene "CollisionSystemTest"
2. Enter Play mode
3. Observe Console window

Expected result: "Entity Entity(1:1) collided with entity Entity(0:1)" are thrown
Actual result: errors are thrown(more detail in the notes)

Reproducible with: 2019.3.1f1 (0.2.0-prev.18, 0.5.1-prev.11), 2020.1.0a22(0.5.1-prev.11)
Could not test with: 2019.2.20f1(0.1.1-prev) and older (due to Entity errors in the console window)

Notes:
[2019.3 errors]
InvalidOperationException: The previously scheduled job CollisionSystem:CollisionSystemJob writes to the NativeArray CollisionSystemJob.UserJobData.NativeContainer. You must call JobHandle.Complete() on the job CollisionSystem:CollisionSystemJob, before you can read from the NativeArray safely.

[2020.1 errors]
InvalidOperationException: The previously scheduled job CollisionSystem:CollisionSystemJob writes to the UNKNOWN_OBJECT_TYPE CollisionSystemJob.UserJobData.NativeContainer. You must call JobHandle.Complete() on the job CollisionSystem:CollisionSystemJob, before you can read from the UNKNOWN_OBJECT_TYPE safely.

InvalidOperationException: The previously scheduled job CollisionSystem:CollisionSystemJob reads from the NativeArray<Velocity> CollisionSystemJob.InputVelocities. You are trying to schedule a new job Solver:ApplyGravityAndCopyInputVelocitiesJob, which writes to the same NativeArray<Velocity> (via ApplyGravityAndCopyInputVelocitiesJob.InputVelocities). To guarantee safety, you must include CollisionSystem:CollisionSystemJob as a dependency of the newly scheduled job.

And many more