Microsoft 365 Office Office Add-ins Office Scripts

Office Add-ins community call–February 10, 2021 

February’s call, hosted by David Chesnut, featured the following presenters and topics:

  • Juan Balmori showed how to set up compatibility between an Outlook add-in and its COM/VSTO counterpart.
  • Abid Rahman announced that the team is looking into building out Word APIs. He created a Word Extensibility Survey to gather feedback on top scenarios and blockers for developers.
  • Aishwarya Iyer provided an update on PowerPoint APIs progress, including what APIs are released, in preview, and under development.
  • David Chesnut showed a new PnP sample that demonstrates how to build a contextual tab that only appears on the Microsoft Excel ribbon when the focus is in a table.

Watch the call


We welcome you to submit questions and topic suggestions prior to each call by using our short survey form.

Outlook add-in compatibility with COM/VSTO

You mentioned a registry entry option to suppress the web add-in if a COM/VSTO add-in is present. Does Excel, Word and PowerPoint also require a registry entry?

That option is only available for Outlook add-ins, for now.

Will VTSO be phased out over the new office add-ins in the future? Or are both planned to be supported indefinitely?

VSTO will continue to be supported. Depending on your scenario, a web add-in can be an awesome alternative for your Microsoft 365 customers, take advantage of cross-platform support, and improved deployment management.

Word APIs discussion

Do you have plans to make the “Show as saved image” content pane feature available from the API? Also, it would be great to have this function automatically triggered in case the required add-in is not available/installed in the system.

If referring to the “show as saved image” capability for content add-ins, we haven’t had an API ask for that specific capability. It would be great if you could log a request on Office Developer Platform UserVoice. The second idea is a great suggestion, as it can make the experience better for users on the downstream version. Can you log a UserVoice request for that as well?

How long will the survey form for Word APIs be open?

We can keep it open until the end of February. If you need additional time, please let us know during the March community call and we can follow up directly.

PowerPoint APIs Updates

How do you get access to the beta channels for PowerPoint?

You’ll want to become an Office Insider. And we recommend that you get a tenant on the Microsoft 365 Developer Program.

Contextual tab PnP sample

Can the contextual tab get auto selected?

Custom contextual tabs show or hide on demand based on an API call. They are hidden by default. The guiding principle we have is to provide an experience for custom contextual tabs that is similar to regular contextual tabs. For example, when you select a table in Excel, the “Table Design” tab shows but it does not have focus. Custom contextual tabs follow the same principle.

Can we localize the labels in contextual tabs?

Yes, for more information, see the localization section in Create custom contextual tabs in Office Add-ins (preview).

Can contextual tabs display info in the task pane?

Yes. When your JavaScript function is called (such as in response to the user selecting a button on your contextual tab) it has access to the DOM of the task pane and can make updates.

Does the function called by the contextual tab run in the same process as the task pane?

Yes. The add-in uses the shared runtime so that all code is sharing the same JavaScript runtime. For more information, see Configure your Office Add-in to use a shared JavaScript runtime.

Miscellaneous questions

Is it possible for an Office Add-in to run Node.js processes, such as reading a database?

You can have a web app/server side process running Node.js that can reach out to read the database. For example, see Create a Node.js Office Add-in that uses single sign-on.

In Excel there seems to be a data connection wizard. Would it be possible to reuse that wizard in an Excel add-in?

No. We don’t currently have data connection APIs. We are considering APIs that let you refresh existing models in Power Query, however. It would be great if you could log a request for this on Office Developer Platform UserVoice.

Our customers have a persistent ADD-IN ERROR that we think is caused by a corrupt legacy Microsoft Edge installation, and the only solution is to rebuild the user’s Windows profile. Users are unable to upgrade to a newer Microsoft Office to enable WebView2, so they are stuck with the error. Please check for more details in GitHub issues 1620, 1356, and also this StackOverflow thread.

We are continuing to investigate the issue. The only current workaround is to update to Webview2. We understand this is not an ideal workaround and will share more once we have an update.

For the addFromBase64 API in Excel, what is the status of opening a collection of worksheets with the current workbook online? Is it going to be on production soon?

Yes. The team is actively working on this feature and we are targeting it to launch with our next Excel 1.13 API requirement set, which will be in about a quarter.


From February’s call

Office Add-ins community call

Office Add-ins feedback

The next Office Add-ins community call is on Wednesday, March 10, 2020 at 8:00AM PDT. You can download the calendar invite at

Engage with us

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David Chesnut