Short version:

This new Outlook on the web feature will bring you an updated experience when receiving email attachments. Microsoft are updating the look and contents of the attachments, and consolidating all options under a single menu (similar to Outlook for Mac and Outlook for Windows). This feature will rollout early to mid-May for most of us.

Details:

This new Outlook on the web feature will bring you an updated experience when receiving email attachments. Microsoft are updating the look and contents of the attachments, and consolidating all options under a single menu (similar to Outlook for Mac and Outlook for Windows).

Additionally, if you are in a tenant with OneDrive enabled you will see new options in this menu and in the attachment previewer for Word, Excel, and PowerPoint files. This will provide the ability to directly begin editing Office attachments in the corresponding browser or desktop app.

This release will enable you to better collaborate by expanding how attachments look (icons have been added to menu) and what you can do with them. The hover over menu has been replaced with a single, always present click target for all actions.

Users can access PreviewEdit in BrowserEdit in Word desktop appSave to OneDrive and Download. Clicking Edit in Browser or Edit in Word desktop app, saves a copy of the file to OneDrive and opens it in the corresponding web or desktop app. Once users make edits, they can then share back collaborative links with co-workers so others can work on the same file in real time.

New attachments with always present click target:

Edit in browser is new default option:

Edit in browser is new default option:

Note: The change to replace the hover over menu with the always present click target will affect all users, not just companies with OneDrive. Non-OneDrive teams will not see the Edit in browser or Edit in Desktop app options in this menu.

Availability:
This feature will rollout early to mid-May for most of us.