Dear Microsoft 365 Developer Team,
I would like to submit a feature request regarding custom menus in Word JavaScript Add-ins.
Currently, when defining custom menus for the ribbon via the manifest.xml, it is possible to create a root-level menu control with a list of menu items. However, submenus (nested menus) are not supported. This limits the ability to create well-structured and user-friendly menus, especially when dealing with more complex add-ins that require logical grouping of actions.
Use Case Example:

Imagine an add-in that handles document templates, formatting options, and insertion of custom content. It would be much more intuitive to organize these into hierarchical menus like:
My Add-in Menu
|
|---Templates
| |---Contract Template
| |---NDA Template
|---Formatting
| |---Apply Header
| |---Apply Footer
|---Insert
|---Clause
|---Placeholder
Currently, to achieve something like this, we either have to create long flat menus, which are less user-friendly and harder to navigate, or define multiple root-level menu controls as a workaround. However, having too many root-level menus clutters the ribbon and makes the overall user experience confusing and less efficient.
Feature Request:

Please consider adding support for nested menu structures (submenus) in Office Add-in command definitions. This would:
- Greatly improve user experience for complex add-ins.
- Allow better organization of actions and commands.
- Align the Add-in UX closer to the native ribbon and menu experiences in Office apps.
Possible Implementation Suggestions:
- Extend the Menu control to allow nested Menu or MenuItem elements.
- Allow referencing predefined menus to enable reuse and modularity.
Related Documentation:
Thank you for considering this enhancement. It would be a huge step forward for creating more powerful and user-friendly Office Add-ins!
Best regards,

Ingo
I'd like to get this added to all the hosts, WXPO, as part of the Ribbon definition. Preferably with the option to dynamically populate the menus, but multi-level menus are a good first step.
