I have tried to register using Facebook on your site, and it seems that i didnt hit that error as you can see here https://screencast.com/t/rvBCRBxzrWsh. Please advice.
it seems that i have replicated this in both mine and your site, it seems that i cant replicates those issues you faced above as you can see here https://screencast.com/t/QMyPhdvDv8qj. I have tested both Joomla and Facebook user. Maybe you can provide us with which user you faced this kind of problems. Please advice.
I am not sure how to replicate this, maybe you can try to clear your browser and site cache first and see how it goes. If problems still persist, please provide us with that images your tried to upload to your site. Please advice.
You are most welcome. Glad to hear that your issue has been resolved now.
As a gentle reminder, kindly start a new thread if you have any other issue in the future so it will be easier for us to manage your inquiry. I will lock and mark this thread as resolved.