You don't need web workers, you just need to host each app in a sandboxed iframe. Then it can render however it wants with normal DOM access and have script and

You don't need web workers, you just need to host each app in a sandboxed iframe. Then it can render however it wants with normal DOM access and have script and DOM isolation from the OS and other apps. You would need some sort of IPC system on top of postMessage, and probably some way to send theme data down into the frame and get things like content sizes back out. I don't think same-origin iframed apps would be out-of-process in Chrome yet, but I do think Chrome is supposed to get out-of-process frames eventually. That would prevent an apps from exploiting a browser bug to take down the whole tab.