New
#11
One workaround is to never logout from OWA.
The very first time you login to OWA while using a specific browser, it asks if you want to stay logged in. If you answer "yes", then whenever you access your organization's OWA page from that browser, it'll immediately open OWA and show your mail. If you have Teams open in a tab of that browser, that'll usually (but not always) open immediately, too, There'll be no login prompt and no extraneous junk shown by the O365 Web site. If you want to leave OWA, just close all of that browser's windows. (RMB the browser's icon in the Taskbar and select "close all windows".)
Of course, you should only do this on computers where you can secure your access to the computer itself.
I use Waterfox for this, with its Home page set to be OWA and Teams on a second tab. They're the only things I use Waterfox for, except for occasionally opening a work-related link. Any other links that I want to look at I copy and open in another browser: Firefox with the NoScript plugin. As a result, Waterfox acts much like a local installation of Outlook would, although with a somewhat different user interface.