I have the same problem here. I was working on my VR game, it game mechanics is player upgrade with a bigger size. Everything in 4.17 is normal and in 4.18, when I upgrade, the VR screen total go flashing and have ghost image between two eyes!
The most tragic thing is, I added new content for my game recently, has been working on 4.18 for a month, crashed 160 times, is going to update on Steam, now actually told me the entire game cannot play now…
And now I am absolute cannot go back to 4.17…:(:(