Wireframe Masks
There are masks that can be applied to masters and some widgets on the wireframe to help identify them.
Masters
To toggle the appearance of a pink mask on master objects on a wireframe, click Wireframe->Mask Masters in the main menu. Masters will have a grey mask if they are placed in the background.
Image Map Regions
To toggle the appearance of a green mask on image map regions, click Wireframe->Mask Image Map Regions in the main menu. Without a mask applied, the image map regions are not visible.
Dynamic Panels
To toggle the appearance of a blue mask on dynamic panels, click Wireframe->Mask Dynamic Panels in the main menu. If the dynamic panel is set to hidden, the mask will be yellow.