I'm hoping someone who has some experience in the Chrome/Firefox extension can save me some time by explaining whether or not this is a feasible idea.
Ok, so when you click the facebook connect button on a site, it launches the OAuth dance and pops a window to a URL with a parameter called "perms" that lists the Facebook extended permissions the app is requesting.
The extension, then, would have to access the DOM to insert checkmarks next to each permission option, and build a new URL based on which ones were selected, and refresh the popup. This will probably break some Facebook apps, but that's fine.
I've read over the Chrome extension API at http://code.google.com/chrome/extensions/getstarted.html and it doesn't seem feasible to do automatically, unless I check every single page URL of every new opened window (maybe I'm missing something though). Is there a good way to do that?
If not, having a button would probably be fine too.