[Plugin: Simple Facebook Connect] FB login button has extra code ("fb:intl")

That’s not extra code, those are XFBML tags for Facebook to allow for internationalization. If they’re showing up on the page itself, you have something else interfering with the code display. Try disabling other plugins.

Thanks for your reply. The code seems not to be showing any more, before I even had a chance to start disabling plugins. So I don’t know what caused the problem in the first place.

Thanks as well for your excellent plugins!

It’s happening to me as well. I have disabled all plugins except this one and the problem persists.

https://imageshack.us/photo/my-images/52/facebookproblem.png/

Try the development version. I removed that code.