We here at IGLOO like FireFox. We had our QA team upgrade to the latest version of Firefox and test it out and we determined that it is not completely compatible.

We have discovered an issue similar to an issue in Internet Explorer 9 where a user will not be able to access their community. Once logged if a Users session times out and they navigate away from the community when they come back to the community page they may be greated by a redirect error that prevents them from accessing the community.

If you encountered this error clearing your browers cache may resolve it temporarily for you. To prevent this from continuing you will have to downgrade to FireFox 4. 

We are working to correct this issue and hope to have it resolved for our July 16th release.

Thank you for your understanding and patience.

Bryan

IGLOO Support