Thanks for letting us know! We're happy to hear that.
We've changed the product quite a bit in response to the huge projects that our users create on our design platform. Nevertheless, we've also faced quite a few engineering issues in respect to browser performance and real time backend data synchronization.
We're still bootstrapped and fairly small (< 25 employees including the founders). We've grown organically to about 1 million users since then. The feedback we've got on our submission back then gave us enough courage to go from just a pet side-project to a full time business, so Big Thanks HN! That day was one of the happiest days in the history of our business.
Moqups[1], our HTML5 based mockup/wireframing app, is completely free for education, non profit and open source projects. To our great surprise, we get a fairly large amount of requests each week from many universities and from open source developers. Aaaand we're happy to fulfill all of them :-)
It's probably because Firefox does not support many presentation attributes as well as proper font antialiasing for the text and tspan SVG tags. It looks like they did create their own text layout engine with support for flowing around arbitrary shapes.
I'm curious how well this works, since emulating native text capabilities (just think RTL vs LTR) requires an insane amount of Javascript and the performance is pretty terrible for texts longer than a few hundred words. If they got this right, it must be a masterpiece of Javascript code. Google recently introduced their own text layout capabilities in Google Docs (also SVG based) and it's pretty buggy beyond simple text. Just to highlight the complexity of the issue, they used to render text into SVG on the server until recently.
It's one of the reasons we had to use foreignObject with pure HTML inside for Moqups instead, although it prevents us from supporting IE at all, including IE 11. We can at least target Webkit/Blink & Gecko this way.