A basic implementation here: <a href="http:&#x2F;&#x2F;webpass.rkeene.org&#x2F;" rel="nofollow">http:&#x2F;&#x2F;webpass.rkeene.org&#x2F;</a><p>A couple of difficulties your writeup doesn&#x27;t cover:<p>* password expiry&#x2F;rotation - webpass uses the &quot;sequence number&quot; for this, and sequence numbers can be saved in localStorage or shared online through another channel<p>* policies.  The &quot;Site&quot; dropdown references a json structure which can specify min&#x2F;max lengths, character type rules etc<p>The implementation is pretty simple, but that&#x27;s kinda the point :).