There appears to be an issue which, after reading through your forum, still persist.
This issues is accessing the https://twitter.com/settings/widgets.
The issue started to occur after I deleted a widget and attempt to create a new one.
The below screen appear.
This problem is account related and not browser or location. I have tested this from various computers / device, on different networks and this error still occurs.
My guess is it a database issues where a value has not been updated in a table and the website method call to return the details is causing an error.
Can you please URGENTLY look into this.