The current edition of ZS has a pop-up filter list that disables the pop-up window for specific browsers. You can also turn the pop-up window off entirely, which will keep all activity up to the redirect to the original site in the original window.
On the Captive Portal config page, look for a ‘popup’ button. This gives you the list of exempt user agents and three pop-up modes: all, none, or all but listed.
In my recent experience, if I set this to ‘none,’ then no one gets a pop-up window. The logged-on user remains on the logged-on list up to whatever the time limit is, even if they close their original browser window.
I asked in a recent post if the pop-up is even necessary in an environment where I want to just grant free but timed internet access to everyone. There was another post that showed how to hide the username and password fields, and just use a generic account for everyone and track connections by IPv4 and MAC address. I assume if you have normal user accounts, you could do away with the pop-up as well.
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