Unreliable Skin Mesh Renderer in Play Mode. causes computer to hang + black screen

I'm running 2018.3.0b6 and certain times when I make my camera scan over a skinned mesh renderer (not a character, just a 3d model I've made that has a skin), Unity hangs. If it hangs long enough, it goes to a black screen and I have to restart the program.

I've tested this on two different machines, and I can confirm that it only happens when my main game camera brings a skinned mesh renderer into its view. Sometimes it will be fine (as in previous versions). But it is unreliable and leads me to believe it is a bug.

Anyone else having this issue?

 

As I'm trying to figure out how to effectively isolate my problem using the Minimal Reproduction tool, I'd like to give more information so that maybe someone on the forum can see if this is indicative of a relatable issue.

Specifically, the player is fine when it first starts up and tries to render the skinned mesh render, (which has four blend shapes), but then I notice the issue happening after I've run the player several times. The amount of times it takes to trigger the issue is somewhere between four and five. This not only includes viewing the item in the scene but also viewing it as a prefab in the preview window (specifically, I'm spawning this object as a prefab, with several components attached).

When it happens, not only does it basically freeze my computer, but other elements in the scene stop rendering, leaving only the skybox. If I somehow manage to get the camera to pan away from the object, everything reverts back to normal. If I leave the camera on the object for too long, the entire unity window turns black and I need to restart. Broadly, this issue can occur in the editor, player and preview windows.

Do you think this is a symptom of my video card running out of memory? Since it has happened on two separate computers, do you think it could be something like a memory leak as it pertains to certain skinned mesh renderers with blendshapes? To date, I've noticed this issue on two separate .fbx objects I have in my scene, and only since upgrading the project to 2018.3.0b6, though it could have been a silent issue when I switched over to 2018.3 last month.

I'll continue to try to scope the project down to the minimal reproduction, but it's a big project, so I'm just trying to throw out useful info in the meantime.

thanks!

 

I made a minimal reproduction project and filed this as bug 1095836.