This article explains how to extend your virtual desktop to multiple monitors when connecting through the browser at mypc.jetlinx.com
Select the pull tab from the side of the browser window
Select the 3 lines/dots button, and select Multi Monitor
A menu will appear for multi-monitor, click on the Add Display button and a new window will appear.
Drag this window to the second screen and press the icon to add that display.
Return to the main window and the Multi Monitor settings should update to display you have 2 screens. Select OK
Your virtual desktop will size up to use the full screen of both your monitors. To escape out of the full screen, drag your mouse to the top of the screen and a X will appear. Select this to exit full screen mode.