How did canvas+JS do? Implementing the export was a lot easier: for the original version I had to write a PNG encoder from scratch in Actionscript! Everything else was harder. Canvas has a feature set similar to Flash 5, so I missed the rich standard library of modern Flash. Using CSS for layout is still inferior to Flex or MinimalComps for GUI design, as any web designer will tell you with even the slightest prompting.
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