Creating _Name file/folder does not work in 4.16

Good evening Epic Team,
I’ve just installed the latest 4.16 and it seems that the underscore key is not allowed anymore has a first character for my files or folders naming convention in Content Browser window. For example, _Main is my main folder where all mesh, audio, maps, blueprints, etc. can’t be named like that in Unreal unless I create it at the source of my explorer window and then open my project Unreal project or create a 4.15 project and convert it afterwards. Will it be a problem in the future if I continue to create outside of Unreal my _Main folder and then run Unreal?
Thanks!

I have the same problem… Why on earth was it changed?

I’d like to hear an explanation to this seemingly bizarre change as well. Is this intended behavior? If so, what was the reason?