An object that conforms to the WebPlugInContainer informal protocol. This object is used for callbacks from the plug-in to the enclosing application. If WebPlugInContainerKey is nil, no callbacks will occur.
Available in Mac OS X v10.3 and later.
Declaration Syntax Version Information- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)