By "extension", we mean any data that can be placed in the input XML document that is not addressed by the XSL-FO standard. By having a mechanism for supporting extensions, FOP is able to add features that are not covered in the specification.
The extensions documented here are included with FOP, and are automatically available to you. If you wish to add an extension of your own to FOP, please see the Developers' Extension Page.
Please see the SVG documentation for more details.
To use this standard FOP extension, you need to add a namespace entry for http://xml.apache.org/fop/extensions on the root element.
You can provide outlines inside the root object (but outside any page-sequences or other formatting objects). Here's an example of an outline entry:
It works similarly to a basic-link. There is also an external-destination property, but it isn't supported currently. See the pdfoutline.fo file in examples/fo/basic for a more complete example.
Please see examples/fo/basic/contlabel.fo