You can open multiple project files for quick reference. By default files are overlaid. Click a page tab to bring a file to the top.
Comparing drawings side by side - click the page tab and drag it to one side, top, or bottom of the window. A shadow of the drawing gives you an indication of how the drawings will be arranged before you release the mouse button.
Returning to overlaid configuration - drag one tab to the other title bar. The shadow will appear only on the title bar, then release the mouse button.
