Support for "Save As" Dialog with Script-Suggested Folder Path in Office.js for the New Outlook

Description:

We would like to request a feature in Office.js—specifically for the new Outlook experience—that allows an add-in to invoke the native "Save As" dialog with the ability to suggest a folder path and filename. The user would still confirm the final location, ensuring security and user control. This would enable smoother workflows for exporting emails or documents to structured folders (e.g., client folders, project directories) without requiring full file system access or manual browsing.

Use Case:

In the new Outlook, we want to export an email and prompt the user to save it in a predefined folder (e.g., \\network\clients\ABC\emails). Currently, we can only trigger a download and the user must manually browse to the correct location, which is inefficient and error-prone. This is especially important in enterprise environments where structured storage is critical.

Benefit:

This feature would bridge the gap between VSTO and Office.js add-ins, enabling more enterprise-grade solutions in the web add-in model. It would also align with the productivity goals of the new Outlook by reducing friction in common workflows.