_NT_SYMBOL_PATH cannot be disabled
After the nearest update, _NT_SYMBOL_PATH becomes a option in DEBUG symbol path config.
But I cannot disable this option or delete it.
Clearly it is a new feature of this update, but is there something wrong that I cannot choose to not use it as a symbol file source?
(In windbg, I configured this environment varible to Microsoft Symbol Server, it's very slow when network is bad)