Question Add a button via plugin?

Simple deal.. I would like to add a button under the avatar (like where the PM button, and online/offline buttons appear) for a "social-site link". Where in Community Builders Profile Manager there will be a tab called cb_socialsite which the user can enter the URL, and in turn, if the field is filled, the "social link" will be clickable, otherwise it'll be grayed out.

The actual question I have comes in two parts. First, is there a way I can make this some sort of plug-in (does kunena have plugins?) or does it HAVE to be done via a hack? Not too afraid of that, I've hacked it to get my JAwards up on there from the old FB days. Just would prefer a method that doesn't mean I'm hunting and scouting code every time there's a Kunena update.

Second, how would I go about coding something like this? I know the basics in human language, but not sure how to code it.. Essentially it should:

read each posted msg in the thread, check cb_sociallink for data, display haslink.png and make url out of it. If cb_sociallink is blank, display nolink.png and be done.

Thanks in advance,

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