btw I'm no longer seeing this bug between box collider and circle collider collsions, only between circles.

This is not completely fixed in 2018.3.0b5 as said in the release notes.

Still often return 0 for both impulses.

When it does return 0, the relative Velocity is oddly VERY high.

I'm seeing this about 20% of the time with big and medium hits between to circlecolliders

This is also all true of contacts[0].tangentImpulse. Whenever normalImpulse returns 0, so does the tangentImpulse.

Further, it's not a different contact. I've checked contacts[1] and up, they don't have anything at all (null), when this problem occurs. So it's simply a problem with lost contact information.

This is a HUGE problem for dynamic game sounds that are based on the extent of physical responses. Please fix.

It's comically obvious if/when sounds are based on these values.

Where is this fixed? Still occurring in 2018.3 betas.

Frequency is about 20% of same sized collisions when they're moderate hits. About 10% for lesser hits and about as much as 50% for heavy contacts.