Migrating to release 3.4 To 3.4 DITA-OT 3.4 includes an official Docker container image, a separate plug-in for PDF indexing, a new option to skip HTML5 cover pages, and initial support for project files that allow you to define multiple deliverables in advance, and publish them all at once.
This topic provides a summary of changes in DITA-OT 3.4 that may require modifications to custom stylesheets or plug-ins. For more information on changes in this release, see the .
New indexing plug-in

DITA-OT 3.4 extracts the PDF indexing code to a separate org.dita.index plug-in, and adds a new depend.org.dita.pdf2.index extension point that can be used to add custom index processing targets to PDF output.

The built-in index processing has been disabled and deprecated. If you have overridden index processing via the transform.topic2fo target in the past, you can set the new org.dita.index.skip property to and re-enable the transform.topic2fo.index target with feature extension="depend.org.dita.pdf2.index" value="transform.topic2fo.index"/ in your plug-in configuration.

 New plug-ins Plug-in Source code location org.dita.index
Legacy plug-ins removed TocJS deprecated features TocJS plug-in plug-ins TocJS

DITA-OT 3.4 no longer includes the following legacy transformation plug-ins in the default distribution:

Legacy plug-ins Plug-in Source code location TocJS troff

To re-install the plug-in(s) from the plug-in registry at , run the following command(s):

dita --install=com.sophos.tocjs dita --install=org.dita.troff