This guide only works for Chrome.
Login in Chrome is not possible without error.
The Outlook addon takes advantage of the LocalStorage of the browser. If it is disabled, the app hangs during login.
Step-by-step guide
You have to add an exception to allow the use of LocalStorage for the addon.
- Visit the Chrome Content Settings: chrome://settings/content/cookies
- Add "https://office365.yasoon.com" to the allow list.