I have a couple of users that use a shared email address with the Outlook for Web Application. When this is left open overnight, for some reason, it starts to fill the storage of the PC until the PC's storage is maxed out and unusable. We found that simply closing the Outlook for Web tab in Firefox fixes the issue, until it's left open overnight again and starts filling the storage again. The issue doesn't happen in Chrome or Edge, both users have the most updated versions of Firefox, and I've followed all of the steps I could find to clear website data. Nothing has made a difference. I talked to Microsoft Support about the issue, and they told me to use another browser, but the users only want to use Firefox (which I understand). Any help or knowledge with the issue would be fantastic. I attached some screenshots of the memory increasing on the PCs to help show what is happening. Thanks!