Add support for WSL (Windows Subsystem for Linux)

[Melatonin64]

If it's possible to detect at runtime that the current platform is bash on Windows, the latest Creators Update allows launching Windows applications from within bash.
See this article.

Running explorer.exe "https://google.com" on bash seems to work - it opens the URL in whichever browser is configured to be the default.

[styfle]

I believe this is fixed in opn found here: https://github.com/sindresorhus/opn

[Melatonin64]

It indeed works with opn, thanks for the tip!