Represents the "ExtGState" entry of the resource dictionary object.

It is an optional entry defined as part of the PDF 1.0 specification.

It contains an Element.

For definitive details see:.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 33, page 83.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 34, page 112.

The ExtGState entry maps resource names to graphics state parameter dictionaries. A content stream activates a named graphics state set using the gs operator, which applies all parameters in the referenced dictionary to the current graphics state.