Add-In Error: Content is blocked because it isn't signed by a valid security certificate in Outlook 365

Currently I am developing my custom add-in for outlook 365/

Then I am trying to use it for testing for example it shows me error. I investigated and found what it opens addon in iframe in edge browser. So question is how to add certificate/s to edge to allow my app to work in it?

I am using :

• Outlook 365 desktop edition

What I tried

• Switching flag in Edge browser to allow not certified certificates to "work"(same thing was done in chrome and it worked there)

• As suggested in comments to use office-addin-dev-certs. Well I installed them on my project by using npm install office-addin-dev-certs and then I am trying to verify it by this command office-addin-dev-certs verify it throws error in console see image 3

• exported certificates from chrome and imported them in edge browser and also on my machine . It did not helped.

Well I found the solution. solution was to create and add certificate to app. In desktop outlook aka office outlook for desktop it uses Edge browser as sidebar for Add-ins.

Reason is what browsers need Subject Alternative Name in certificate. So need to create a trusted self-signed SSL cert for localhost (for use with Express/Node) . So the solution was found in this post.