Sometimes when I do VR Preview, it gets input focus (so it can take keyboard and motion controller etc input to the UMG widgets). Other times it does not. If I quit and restart VR Preview enough times, it usually starts working again. What the heck is going on?
I noticed I was getting (Accessed None error from node) error in Message Log. I added an Is Valid check to avoid this, and UMG VR input seems to be working consistently now