How can I set up an autorefresher?

May I do it? I know that's hard to do something like "realtime", but I'm willing to change my forum from IPB to Vanilla but my users think that the "autorefresher" offered by IPB is an essential thing.
In case you didn't know, when you post a new comment in any post on IPB, the system checks if there are new posts and then load them (using something like AJAX).
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this exists in 2.0.18.4, check your settings.
grep is your friend.
Thank you, x00