Edge WebView2 Runtime lets our Store Office Add In fail

[ndee8sh]

Hi there,

we have an Office AddIn (Content Add In for PowerPoint) in the store for a long time.

With this Office Version we get a "Too many redirect" error when the Add In is authenticating:

The add in and the server we are connecting does not have changed.
Now I simply de-installed the Microsoft Edge WebView2 Runtime (89.0.774.76)

Now our Add In works again like expected.

Any ideas or is this just a bug in WebView2?
Thanks, Andi

[#2 · Accepted solution]

The redirects in authentication flow are due to a stricter handling of cross site cookies in chromium based webview.
The cookies must set the SameSite-Mode to None and Secure to true to support saving of authentication cookies cross site.

See the complete answer and solution here.