I am using Google Chrome as my default browser. I have a 900 Mbps plus connection to the internet. When I try and log into the app for Outlook I repeatedly receive a "Still not Loading? You either have a slow connection or you're using an unsupported browser." I don't believe either to be the case.
What is the current version of your extension and chrome? Could you please check If it's the most updated version? I would like to share this knowledge base here with more information about how to troubleshoot to outlook desktop extension.