New version releases of browsers don’t get the buzz they used to get, but Firefox Quantum is an exception. The latest version of the Mozilla Foundation’s browser, released Tuesday, is all about performance. Firefox is twice as fast as it was a year ago, Mozilla claimed. It is not only fast on startup — it remains zippy even when taxed by multitudes of tabs. “We have a better balance of memory to performance than all the other browsers,” said Firefox Vice President for Product Nick Nguyen.