UNC = "\" host-name "" share-name [ "" object-name ]
host-name = IPv6address / IPv4address / reg-name
; IPv4address, and reg-name are as specified in [RFC3986], see following for IPV6
share-name = 180pchar
pchar = %x20-21 / %x23-29 / %x2D-2E / %x30-39 / %x40-5A / %x5E-7B / %x7D-FF
object-name = path-name [ "" file-name ]
path-name = 1255pchar
file-name = 1255fchar [ ":" stream-name [ ":" stream-type ] ]
fchar = %x20-21 / %x23-29 / %x2B-2E / %x30-39 / %x3B / %x3D / %x40-5B / %x5D-7B / %x7D-FF
stream-name = schar
schar = %x01-2E / %x30-39 / %x3B-5B /%x5D-FF
stream-type = 1schar
https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-dtyp/62e862f4-2a51-452e-8eeb-dc4ff5ee33cc
it is implemented in the electron build as dependency named vsda visual studio domain authority i guess.
get imported by bootstrap-* code of vscode src.