Same issue here, I tried changing the editor input settings for the Viewport properties like the above comments but now my FPS character only moves if I click the mouse down.
I’m not sure if your method is the answer because it hasn’t been set as an answered question by other users. For me it almost seems like a workaround until the 4.14.1 patch comes out and fixes everything back (I hope). I noticed there is a case number already out for this but it was updated 2 days ago and it says resolved but i guess maybe they are waiting to release it?