[MouseEvents plugin] Support for back/forward buttons

[leekyuh]

Hello,

In Ubuntu, I used back + left button click to go to the left desktop, back + right to go to the right desktop.
It was very convenient because I can navigate reliably with only one hand.
Could you please add some more extra buttons (back and forward buttons) which in Ubuntu the codes were 8 and 9.

Cheers

[Patrick]

You can switch desktops with the back/forward buttons by clicking on the taskbar or the desktop background.