HTTP 500 on log-in with Google account

I may log-in normally, but log-in with google account fails with following message: “The OpenStreetMap server encountered an unexpected condition that prevented it from fulfilling the request (HTTP 500) Feel free to contact the OpenStreetMap community if your problem persists. Make a note of the exact URL / post data of your request. This may be a problem in our Ruby On Rails code. 500 occurs with exceptions thrown outside of an action (like in Dispatcher setups or broken Ruby code)”.

I am not sure how I can extract post data, but it happens every time I click on google icon on