4
per your screenshot...
I would use the order of accending instead of "ordem descendente" to show the posts first to last. The resulting code then may give you a idea of how to make the call to the first post icon. Looking at the html code in FrontPage.
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or...
modules/newbb/class/forum.php << reading the function display code ....
Brings to mind the last_post_id is the same as the first_post_id if you know how to call only the first entry of the array then don't "continue".
That is a tip, I would give you the exact code if I knew it but I don't. Maybe someone will pick up on it from here or you might be able to adjust it yourself.
Good Luck
BlueStocking
BTW: @John V., Somehow, I think phppp is going to be pretty busy about now. {{grin}}