Camera viewport separated from camera physical position?

I have a bug in my game where the viewport stops updating its position to the camera's position. In game, a behavior moves the camera transform to follow the player, but when this bug hits, the screen is stuck. In the scene view below, you can see that the white frustum is separated from the blue one. The white one remains in place as the camera transform and cyan frustum move. Normally, these are coupled.

Any ideas how this could occur? I'm in Unity 5.6.

Also, what exactly does the cyan frustum represent? I can't seem to find any documentation on that.

Thanks for any help, you might save today's demo!

- Steve

 

The camera's matrix was being manipulated for an effect that, under rare circumstances, got destroyed before it could finish / reset.