[twitter-dev] Getting "400 Bad Request" when I try to update my application settings

Whenever I try to update my application's settings—in this case, I was trying to enable "Use Twitter for login"—my browser hangs for some time, then gives me a 400 error. Is anyone else experiencing this problem?

[twitter-dev] Can't change application settings

I'm trying to enable "Use Twitter for login", but whenever I check the box and click Save, my browser just hangs and I am redirected to a blank /oauth_clients/update page. Is anyone else experiencing this problem?