From time to time, you may want to impersonate a user in the system. See what he sees, see how his Security Roles affect the system and/or recreate a security role related error.
Unfortunately, there is no supported Microsoft way of doing that, so you have to resort to 3rd party solutions.
You can for instance use the ModHeader browser extension to change the current user’s Azure id. There are several instructions on the web that explains how to do that. It’s not all that easy to manage if you need to impersonate a lot of users, so I don’t recommend that approach.
The best way in my opinion is to use the Level Up for Dynamics 365/Power Apps browser extension which I have written about here: Level Up for Dynamics 365/Power Apps – It contains a nice user impersonation feature.
As with other solutions, it’s not a Microsoft supported impersonation feature, so it’s not 100% stable, but it works well enough and can be of big help in the above mentioned scenarios.
Anyway, Start by opening the CRM app where you want to impersonate the user, for instance the Customer Service Hub:

Open the Level Up for Dynamics 365/Power Apps extension. I assume you have already installed it, if not, you can read more about it here: Level Up for Dynamics 365/Power Apps

You’ll find the impersonation feature in the top of the sidebar. Use the Search Users field to search for the user you wish to impersonate:

Once you see the user you wish to impersonate, select him/her in the search results:

Then click the “Impersonate” button:

And that’s it: You now see the app as if the selected user was logged in. Level Up tells you that an impersonation is ongoing and you can tell from the information in the upper right corner of the app that it is now the selected user that is active. You stop the impersonation by clicking the Stop button of course.

OBSERVE: If the user you have selected doesn’t have security access to the app you’re in, the impersonation feature will not work. Therefor it’s a good idea to keep an eye on the user information in the top right corner.
It may also be that the impersonation doesn’t work straight off and you may have to refresh the browser page once or twice.
Good luck, and don’t do anything stupid during the impersonation… 😉