This app fixes the problem of having two O-365 accounts and MS not being able to keep them separate. Also great for reducing the number of cross-site tracking and marketing. I don't get as many ads for things I've already purchased as I used to. The only issue I have with it is that you can't pin an entire subdomain to a container. If a site uses different hostnames for different functions, you have to specifically pin each one (AWS does this a lot). If you lock the container so other sites don't accidentally open in it, you also can't open a new hostname under a domain that's already part of that container.