By the way, these concepts of localStorage and sessionStorage are new to me. Evidently they're something like glorified large cookies in HTML5. Chromium handles it just fine, but I don't think my Firefox browser even understands it yet. I see where I can examine all my live cookies there, but I don't see any mention of "storage" there. (I'm using Firefox 3.6.24 on Ubuntu.)
Consequently I haven't been able to get it to work yet on FF. But maybe that's because long ago I did a bold yet insane experiment wherein I deleted all trusted root CAs in that browser. So it might be my problem, not yours.