German platform deskmodder.de reports that Mircosoft is experimenting with PWA (Progressive Web App) versions of their office suite with some users. According to the author of the article, PWA versions of Excel, PowerPoint, Outlook and Word appear in the startmenu.
It turned out that these apps were created by Microsoft Edge (Stable). The path of the apps points to C:Program Files (x86)MicrosoftEdgeApplication. Apparently, the PWAs are started by msedge_proxy.exe.If you start the apps, you’ll be redirected to the login page: https://login.microsoftonline.com. After the login, you can work with Office documents.