Starting with the release of Strategy ONE (March 2024), dossiers are also known as dashboards.
SYMPTOM:
When a dataset that contains at least one custom group or consolidation is used in VI, the option to create attribute is not displayed when you right click on the attribute.
STEPS TO REPRODUCE:

CAUSE:
This is an identified defect in Strategy Web 10.6 and below.
ACTION:
This issue has been addressed in Strategy Web 10.7 and above. Upgrade to any of these versions to be able to create derived attributes out of a dataset that contains Consolidations or Custom Groups.
Note: This fix has been implemented for Strategy Dashboard/Dossier and not Report Services Documents.
KB440882