How to display subforums inside subforums??

Does anyone know how to setup forum listing display depth of subforums inside subforums?
Kind of like this idea.

MAIN FORUM
--SUBFORUM
--SUBFORUM
----SUBFORUM
-------SUBFOFORUM
-------SUBFOFORUM
MAIN FORUM 2
--SUBFORUM
----SUBFORUM
-------SUBFOFORUM
MAIN FORUM 3
--SUBFORUM
----SUBFORUM
-------SUBFOFORUM

I can't figure out how to play with subforums depth.
I tried 3-3-3 and 2-3-3 but it seems it doesn't work, even if I rebuild the thread information.

Anyone knows how?


How to display subforums inside subforums??
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s2pidkaspr

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