Microsoft 365 Office 365 Add-ins

Office Add-ins Community Call – May 13, 2020

May’s call, hosted by Alex Jerabek, featured the following presenters and topics:

  • Ankush Oberoi, Software Engineer, discussed and demoed the appendOnSend feature for Outlook. This feature allows add-ins to add custom text or HTML to messages when they are sent.
  • Ruoying Liang, Program Manager, demoed the insert worksheets feature, also known as addFromBase64, which adds worksheets from an existing Excel workbook to the current workbook. She also asks developers to fill out this survey to help move this feature from preview to release.
  • Keyur Patel, Program Manager, talked about the new features for Excel Add-ins that are coming soon. These include dialog messaging, shared runtime, and new APIs for Excel features.
  • Alexander Peter, Development Manager at SAP, shared their upcoming add-in for the SAP Analytics Cloud.

Watch the call here.

Questions and Answers

The available information about Edge WebView states that it supports media and recording. Does this mean that audio recording is available also from a MS Word Desktop Add-in? I was able to make it work in an Add-in for Word Online, but when I tried from the Word desktop application I got a “Permission Denied Error”, although I gave the “Desktop App Web Viewer” permission to use the microphone.
Unfortunately, we block media access (microphone, camera, geo loc) on the current Edge Webview. This feature should become available once we move to the Chromium based Edge Webview2 engine (tentatively scheduled for later this Fall).

Ideally, there will be only a short delay between clicking send and when onSend completes before the email is sent. Here, we’re concerned about users editing this within that timeframe, which might be a valid use case if the add-in takes long to execute. We’ll consider it internally, but please raise the issue on UserVoice.

What is the roadmap for adding more VBA / VSTO functionality to Office.js?
We prioritize features based on UserVoice requests. Please create a new suggestion or upvote an existing one.

Is there any news about Chromium-based Edge WebView2? Is there any way to test this in MS Word Add-in?
We’ll share information on this in an upcoming call.  Stay tuned, but we are tentatively targeting to share more info on this during the June call.

We are planning to create a big enterprise software on Office.js as it has better UI capabilities. Will we have any support if we get stuck somewhere in architecture or some other technical support? It is very new technology and I didn’t see many questions answered on forums.
Please use our channels across

How do you debug easily on web browser for a Word add-in?
Please refer to this article, Debug add-ins using developer tools on Windows 10, for information on web-based debugging.

Are the SSO APIs going to be GA on the Outlook 1.9 requirement set?
Our goal is to release this API ASAP, we are actively working on it. I am not sure if it will be included as part of 1.9 or if it will be a requirement set on its own. The latter can happen if for whatever reason we need to delay it more, hopefully not.

Can we get the add-in panel to start automatically when an Excel workbook is opened?
Yes, you can do that with shared runtime once you’ve tagged the document:

If you want to do it also in Word and PPT check out

Are there any plans to support custom functions on the iPad?
We are considering custom function on iPad, but custom functions depend on add-in commands which are not enabled in iPad yet. If there is an update, we will publish it in community call.

Please upvote this UserVoice suggestion to help show the community’s desire. In the meantime, please check out this PnP sample for using a shared library between VSTO and Office Add-ins.

Which UI we should use with angular framework for office JavaScript API?
The good thing about Office Add-in is that it’s up to you to choose the framework you think is best for your add-in.

Can the appendOnSendApi be used without starting the add-in (in the background)?
We are working on an Event Based model you can use in Outlook (we call it Autorun). For instance, when the user creates a new email, you will be able to subscribe an event and call the API from there. Please check our last community call where we talked about this model and how you can try it today.

I can access the context.workbook, but I didn’t find any obvious id to be used externally (like on Microsoft Graph API).
ID is not currently exposed on the API but a good feature request.

To publish an add-in, I use the manifest right? Just to be sure, I need to build the webapp and publish all together and it runs on Microsoft dependencies, or I need to run it on my on server and just provide the manifest pointing to it?
You’ll only need your manifest to publish an add-in. The manifest points the Office host to your web service. You can learn more about publishing in this article.

When can we expect AddFromBase64 functionality to production?
We currently don’t have a release timeline can share. But we are trying to fill the gap in Excel Online and make the API release to production.

Can an OnSend Event be used only on Appointments or Email? Or is the OnSend event triggered for all items in the mailbox?
OnSend is currently only available on email and meetings.­


From May’s call

Office Add-ins community call

Office Add-ins feedback

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

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