Successor view on Roadmap reports

Activating the 'Show successor view' option in the Roadmap report's settings adds additional rows for each successor Fact Sheet to the report.

To quickly grasp what will happen in the future, all successor's names and lifecycle phases are shown below the predecessor, now better distinguishable from drill-downs. We also removed the duplicates generated by successors being shown as drill-downs.

This option can be combined with clustering and the recently released 'Optional Details'.

The following steps will be the removal of Fact Sheets from the report with lifecycle phases outside of the roadmap's timeframe and aligning the aggregation of lower-level hierarchy clusters to the same behavior as in Matrix reports.