Only the Owner can make edits to the workbooks via Tableau Web/Online and Save over existing Dashboard. The other roles, like Project leader, Editors cannot Save over someone else’s Dashboard, Not even the Server Administrators! The Save button will be grayed out for all others when they open the Dashboard for Edit in Tableau Web.

In order to save another users workbook via web, you have a couple of options.
- Take ownership of the Dashboard and then make the edit and save the workbook.
- Or download the workbook and make the edit and republish it thereby overwriting the original(i.e., you become the Owner by default in this case).