Support "chrome.identity" API
Chrome, FireFox, and Opera support the chrome.identity API to handle oauth2 authentication flows. At least the methods launchWebAuthFlow and getRedirectURL are needed to support an oauth2 flow forarbitrary oauth providers siuch as Microsoft, Google, Facebook, LInkedin, etc.
This API is really missing from edge.
Jared Pickerell - Troy Public Schools commented
This is a pretty big extension API to be missing from Edge. Any chance the team is considering getting this added any time soon? https://docs.microsoft.com/en-us/microsoft-edge/extensions/api-support/extension-api-roadmap shows it as "Under consideration".
Any extension that would read and/or write to a cloud based storage provider needs the identity API to authenticate with oauth. One specific example would be the Keepass Tusk extension (allows accessing your KeePass password database to fill forms and authenticate you to sites you have saved your credentials for, a great extension!). It works fine in Chrome and Firefox. As it accesses a Keepass DB stored in at cloud location, it can't work with Edge. https://github.com/subdavis/Tusk/issues/280
Brad Leitch commented
Thumbs up on this: it's hard to consider Microsoft Edge an enterprise class browser when a key feature like this is missing. The default functionality should be to provide identity information for the user currently signed into Windows. Even better, provide an oAuth method that allows a user to sign in using their Chrome identity and have a policy for administrators that enforces users being signed in before they can navigate.