Breaking: #68243 - Move not used FrontendDocumentTemplate
See forge#68243
Description
Move unused FrontendDocumentTemplate to ext:compatibility6.
Impact
Installations still using FrontendDocumentTemplate require ext:compatibility6 to be installed.
Affected Installations
Installations still using FrontendDocumentTemplate.
Migration
Install ext:compatibility6 or adapt the code to not use the FrontendDocumentTemplate functionality.
Adapting the code is highly recommended.