The application does not correctly use the desktop's prefered mail application on the systray's icon click

[jac3n]

When activating the option "execute the mail reader on click", MN opens the desktop's most preferated application if the user click on the systray icon.

But if the command line of the mail reader is whitespace-separated (for me, it's " firefox 'https://mail.google.com/mail/#inbox' " (and it should always be so when you have only *one* GMail account i think), MN just opens firefox as if it could not read the entire line.

Cordially !