All of a sudden I can’t see through vehicle windshields or building windows:
My perception is 10, eye encumbrance doesn’t make a difference, and I have no effects or conditions that I know of. Weather is clear, there’s plenty of light. This was not the case an in-game day ago. Any ideas what is going on?
You’re probably crouching.
Oh, ffs. That was it, thanks.
Haha that happened to me many times, glad there is an icon above my head now, also it’s been the cause of death as the zombies all sprinted up to me as I thought I was running, glad I’m used to it now it is a welcome addition really… But yeah that one had some good growing pains. 
In addition to explaining the crouching mechanic I also show how to change the key bindings to prevent ‘crouch suicide’ (accidentally going into crouch mode). This is especially helpful for long-time players whose muscle memory is hard-coded regarding the Run/Walk toggle.
I was hoping you would make this one specifically. Looking forward to watching it.