[DEMO]
[FEATURE] While in a browser control pressing M1+M3+I opens the current HTML in an external browser

The shortcut is the same as in Safari and Chrome.
On Windows/Linux it is Control+Shift+I.
On Mac it is ⌥⌘I.
[FIX] The external browser loaded HTML using M1+M3+I now also contains includes by ExtendedBrowsers