Fly login through browser UI will "invalidate" existing browser session

[xtremerui]

Summary

When doing fly login by clicking the URL to use browser, fly will be logged in after the auth is done while seeing login successful! page on browser. However, on an existing Concourse UI browser tab, if user tries to do an action that requires auth like pausing pipeline or viewing private resources, user will be prompted to login again.

Steps to reproduce

1. Login to the UI (tab 1)
2. Login via fly cli (tab 2)
3. Try to do something in the UI (tab 1) that requires auth, you will be prompted to login again.

Expected results

user should be able to perform any action in tab 1 without re-login

Actual results

user need to login again

Additional context

There are couple observations for this behavior:

1. on the login successful! tab 2, user can navigate to any Concourse url and perform actions without re-login
2. on existing Concourse UI tab 1, if user refresh the page first and perform an action later, he won't be prompted to login again.
3. on an existing Concourse UI tab from a different browser (or browser profile I guess), the session is not affected

Triaging info

• Concourse version: v7.9 v7.10 v7.11
• Browser (if applicable): firefox chrome
• Did this used to work? unknown