From Geni discussions via Mike Stangel:
"Anyone is welcome to try it out, but because it's not yet an official feature we are not accepting bug reports through Zendesk. We've also formalized the link ("appleseed" was just a development name), so the official link is:
Angus Wood-Salomon The HTML5 tree is still under active development. We'll soon enable a feature to make it your default view, under "Geni Labs". I'll be sure to keep everyone posted
Yes, you have a project about the API here: https://www.geni.com/projects/The-Geni-API/1124
You said "We have to face it: These discussion threads are stone dead and serve absolutely no purpose as Geni obviously and simply does not care about them and has not for years on end!"
I just saw this for the first time, I must tell you that is a very unfair statement you are making, if and when Geni is ready to make an announcement about HTML5 I am sure that you and every user in Geni would hear about it.
It is in the works
Until a few days ago I had a perfectly normal Geni family tree. where I could merge duplicate profiles and their families and such, but suddenly I am offered a HTML5 tree which is completely immobile. The pop-up window says in rather bad Dutch that I am using a "device which is not supported by Flash, and therefore I am being sent to the HTML5 version". My device is Mac Mini with OS X El Capitan and Flash CS4 seems operative... How can I see the old tree again?