Specifies a pattern or keywords that a menu item needs to match to appear in the tab menu inside the network node that has this property. This is a space-separated list of names.
Some network nodes are able to limit the contents of their tab menu inside. They test the mask specified in this parameter against certain properties of the menu item, and include it in the menu only if it matches. Different networks test different properties. For example, material networks may test shader’s render name or its vopnet mask.