The "Move to Folder" option is not available when attempting to move a dashboard to a folder using the 3 Vertical Ellipses menu in the Dashboards section.
Environment
Aria Operations 8.x
Resolution
The correct process to move dashboards is through the "Manage Dashboard Folders" option accessible via the 3 Horizontal Ellipses (...).
To move a dashboard to a folder in Aria Operations 8.x versions:
Go to Operations > Dashboards > Manage (for 8.18.x versions) and Visualize > Dashboards > Manage (for versions prior to 8.18.x).
Select the required Dashboard.
Click on the 3 Horizontal Ellipses (...) menu.
Select Manage Dashboard Folders.
Drag and Drop the desired dashboard to the target folder.