>For instance the security model for a browser should be ultra tight and protect the user from the site, but as a developer I'd want to access and modify my files directly through the inspector panel.
Interesting. I think there is also a plugin for WebStorm to send back modification made in the style panel to the actual files. Sadly sass/less resources makes it difficult to edit CSS and have it applied back to the sass source for instance.
That reminds me: It would be nice if you could open several different incognito windows, each with their own session. That way one can debug user interactions without needing as many browsers as users in the interaction (or half of it because each browser has it's own incognito session in addition to the normal session).
A workaround that I've used before is to connect to my site via the domain name in one tab, and the IP address in another - cross domain protection ensures I get two nicely partitioned sessions.
https://code.google.com/p/chromium/issues/detail?id=328026
>Another example would be the use of cache, where I want the minimum possible retention while a user would want the opposite.
Chrome Inspector -> [x] Disable cache (while DevTools is open)