Click on the NoScript logo, and pick 'allow facebook.net' from the list that pops up. The logo looks like the one at the bottom right in this image:

You probably have an Ad Blocker that's causing the issue. The favorites button is one of the very last items to load on a page, and so if the Ad Blocker stops an advertisement from loading, then quite often the rest of the page won't load either.

If you need more specific help in fixing this, I'll need to know what browser (and version number) you are using. :-)

This page walks you through how to unblock a website. Its easier for you to look at the link than for me to explain. (Just click on the "Show me how this is done" link on that page). :)

Plus, it might be a good idea to update your browser - FF is on v13 now.

I agree with Kiteman's suggestion. You might find upgrading to a newer version might fix the problem altogether.

Okay. Can you just disable Adblock from FF while you are on Instructables and then just re-enable it when you leave the site?

Adblock Lite and Adblock Plus are both available for your current FF version, but perhaps it was not installed (which means its not the problem).

I did some research, and unfortunately, there isn't a whole lot of support for that version, (just a lot of recommendations to upgrade).

What I would do is;

a: Try another browser (if you have one installed), as you may be able to favorite through something other than FF.

b: Use Firefox's bookmarks. You can make a bookmark folder called "Instructables Favorites" and use it to bookmark the ibles.

Unfortunately, I'm not sure how long you have on your current version before you may start experiencing other issues...

You're welcome. There's usually a solution somewhere... :)