To export XSL-FO documents in various formats, XF Designer uses an internal engine.

If you want to use Apache FOP Engine as an external engine, you have to know that there are some constraints regarding the elements that this engine supports.

For example, Apache FOP Engine does not support some elements from FO and all the elements specific to XF and XFD.

In order to avoid eventual errors in generating documents using this specific engine, XF Designer provides a plug-in named FOP Cleaner that prepares the FO document for the engine by erasing all the unsupported elements.

 

To enable the FOP Cleaner plug-in go to File>Options and from the Plugins menu select Ecrion.FOPCleaner as your current export plug-in like in the image below: