Fearful Tumbles

Couple of questions:

1. Why is there not a way for the browser to pass to a website whether certain features are available? Or to run a test on certain features? That way new browsers might work before being officially approved by every bank and site you might need to pay a bill on individually.
2. Does the “javascriptFailure” in the url mean that that this did exactly what I’m asking? Or is it a piece of poor wording that is actually just a sick joke for anyone with enough free time to actually read the URL of a webpage telling you that you failed?