Comment 3 for bug 1833767

I was able to "fix" this problem using Chrome by going into developer tools, selecting "application" tab (in dev tools), highlighting "Clear storage", and the clicking on "Clear site data" in right pane.

It's not immediately clear to me if this is strictly a client side issue, server side, or combination. I'm inclined to think it's both, but the server should probably be able to handle the exception gracefully as it's not uncommon for users to clear cookies or not use them at all.