facebook login giving blank page

Huw,
If you could, turn Error Reporting (in the Global Configuration area) to maximum and see if you can recreate the problem. When you do, post the error. We're looking into a possible new user registration issue when you have the "User Creation" setting configured for "Facebook User Only"... and if you can post your error, that will help us narrow things down.

Sorry for the trouble, but we'll help how we can.

Thanks,
Alex

Well that's obviously not good. Like I mentioned, there's a login issue that we're currently investigating, but this honestly doesn't seem related (the internal recursion thing's a bit odd).

Can either of you send a credentials to your site so we can get in and do a little investigation? You can private message me by clicking the arrow under my picture (<----) and hitting the mail icon. Once in, we'd install a file manager, like extPlorer if not already installed, so that we can make some minor modifications to JFBConnect to track down the issue.

Thanks,
Alex

Thanks to both of you for sending over details so quickly. I struck out on both sites as initially registering and logging back in again went off without a hitch for me.

My guess is that you're running into the login bug I mentioned above. Basically, Facebook gives every user a unique 'token' which we can use to validate that user with Facebook on your site. Periodically, these tokens get out of sync or are invalidated (for many reasons). While we handle most cases of this invalidation, there are times when things get really out of whack. We're investigating this and will have an update out as soon as we can.. my guess would be later next week.

I'm not sure why there's no error being reported on the page that you can see with error reporting enabled. That would help us to make sure it's the same issue. Either way, I'll be trying to login periodically to both sites on the front-end to see if I can catch the error in action, and if so, will try to do some debugging through the admin area. I'll keep you posted if we find anything, and please do the same if you notice any trends or different behavior.

Sorry for the troubles, but we'll get you fixed up soon.

Thanks,
Alex

One other possible thing to try is to change some of the migration settings for your Facebook application. We've tested with the settings below in multiple configurations, and honestly, don't think they have an effect. However, these are what you should be using. To change these, edit your application's configuration at:
developers.facebook.com/apps/

Click into your application, and go to the Settings->Advanced area (in the top left)
Set the following 2 settings (at the bottom of the "migrations" area) to "Enabled":
Forces use of login secret for OAuth call and for auth.login:
Encrypted Access Token:

I think your issue is intermittent, so even if it appears to work afterward, it may not be really solved, but any feedback you have will be welcome to hear.

Thanks,
Alex