Some hints about finding browsers on Windows.

When browsers are installed, they should register themselves in HKEY_LOCAL_MACHINE\SOFTWARE\Clients\StartMenuInternet so that users can change their default browser through the OS.

On 64-bit systems, this is always in the 64-bit registry, so to open it you need OpenKeyEx and the KEY_WOW64_64KEY flag.

Each subkey of the key represents one browser, and the key name is a moniker while the default value of each subkey is a user-friendly name.

Under each subkey is a shell\open\command key that has the path for the browser in the default value. As far as I can tell this must be the path and cannot contain command-line arguments, and it may optionally have quotes (to handle spaces in the path).

I'd expect browsers to provide command-line arguments for opening in an existing window or a new one, but they will differ between browsers. and will require individual research (though it looks like the attached patch has some of them).