Quite handy for doing the annoying bits of this yourself. I don't really like the private key being just available but I also don't have a solution for generating this that doesn't include private keys but is also generally useful.
Yeah, you have a point. For security, implementation goes like this: the keys are generated once for a page load and are not recorded (for obvious reason - security), keys are gone after closing the browser tab, so, as far as tool is concerned keys are ephemeral. To generate new keys simply reload the page.