What versions of SWF does Shumway aim to support? 7, 8, 9, 10, all of the above?
How does Shumway interact with click-to-play and similar mechanisms to stop unwanted Flash objects from playing? Does it have that functionality built-in?
Shumway does not currently support click-to-play because it is not a real browser plugin. It hooks into Firefox's click-to-play mechanism to conditionally override the Flash plugin. This is a hack and will soon be replaced with "jsplugins", a Firefox feature that will allow browser plugins to be written in JS and run in an out-of-process sandbox:
Same process isolation, but the JS plugin got a vastly reduced surface to attack.
From the discussion on HN, it sounds like Shumway aims to be a drop in replacement for Adobe's Flash plugin.