After impersonating a user, the "switch back" pop-up can still appear

Issue Summary

If a site-admin impersonates a user and then clicks on switch back to stop impersonating the user, if you click on browser's back button, the pop-up will keep appearing and the switch back link will not do anything

Steps to Reproduce

1. Impersonate a user
2. A pop-up will appear to switch back to your user. Click on switch back
3. When you're redirected to User Management page, click on browser's back button

Expected Results

The site-admin user should not see the switch back pop-up.

Actual Results

The switch back pop-up will keep appearing even if you close the window.

Note: Some users reported that they were also able to reproduce this issue in a bit different way:

1. Impersonate a user
2. A pop-up will appear to switch back to your user. Click on switch back
3. Close the browser
4. Open it again, and access the Instance. You will be logged with the original account, but the pop up will still appear, and the switch back link will not do anything

Workaround

A manual workaround is to have the admin to navigate to <siteurl>/impersonate, which will reset the impersonate function. e.g. acme.atlassian.net/impersonate