I can't accept your complicated worldview. Iframes, for example, don't need to be new processes. One process - one window - one DOM. The only new process should

I can't accept your complicated worldview. Iframes, for example, don't need to be new processes. One process - one window - one DOM. The only new process should be the rendering canvas/window. An iframe, or any nested resources can re-use cookies associated with a window/process, including caching. In order to persist tokens/cookies/cache between processes you hand them their own copy when you spin them up and write them out to a common, re-usable place when you close, but for the most part I consider browser statefulness to be more like a flaw than a feature (I constantly clear my cookies, form data, and history). how about a "save session" button, rather than the default being to cache objects and cookies in some common blocking profile that only allows one session and that, when it crashes, it all comes down... If you really want to share, you wrap those services up in a library - which is closer to the present model - but you have to know that in doing so you are making it harder to isolate things when they fail... And isn't that what's wrong with most browsers?