Session expire on popup aspx page

I have query over session expire on popup aspx page.
I have asp.net project where session expire funtionality is working. now i have add one new aspx that will open as popup on certain
event on the login page after sign-in process.
Now question is session expire funtionality will also work for the popup aspx page as it inherit same namespace OR
we need to implement some thing else for this
Thanks

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