I had installed Microsoft Planner through Edge's "Install this site as an app" in an Azure AD-based profile. Planner as an app was pinned to my Taskbar. That has worked across multiple computers for a few years (probably since shortly after Edge started letting us install sites as apps). I also had some other non-MS sites installed in my personal profile (e.g., Hulu). This morning, I clicked on the Planner icon and it just opened the Edge browser for the Azure AD-based profile. I checked the Apps -> Installed Apps for that profile, and it lists two of four that are installed in my personal profile.
Other than the shortcut icon still on my Taskbar, there appears to be no record of the MS Planner installation.
I checked my profiles on another computer (a laptop) I use and they no longer match between computers, with one of the two personal profile apps that jumped profiles on my main computer is also appearing in my Azure AD profile on the laptop (but not the other).
I figured I can just uninstall the errant apps and reinstall Planner as an app. However, when I remove the apps from the Azure AD profile, it fully uninstalls them from Windows, removing them from both personal and Azure AD profiles. I will reinstall the personal apps from my personal profile and Planner to the Azure AD profile, but now I'm concerned something is seriously corrupted. Isn't there some security or protection that isolates these profiles from one another? How could apps from one profile migrate to another and then infect the profile itself so the problem also spreads to other computers?
I don't see any reports of this on the Internet. Any ideas how this happened and how to prevent it from happening again? Also, from an enterprise security perspective, the fact that this can happen is concerning. It suggests that profiles are far less secure than I had assumed.