Hi @GRichards4! Welcome to the Community-- happy to have you here 
I am so sorry to hear about the frustration you have experienced setting up this integration. I appreciate you reaching out and providing all of this context. Chrome is typically the recommended browser for these extensions, so I am glad you got that sorted out.
I agree that it is frustrating to not be able to pin the add in. As noted in the Knowledge Base article, you cannot pin the task pane open in the inbox when accessing your @outlook.com email address on Outlook.com. I can see the value of being able to do this through the browser -- I encourage you to consider creating a post on our Ideas Forum here. If you find a similar idea, give it an upvote and share your unique use case in the comments.
Let me know if I can clarify anything else or if you need assistance with the extension in any way!
Best,
Kennedy