I find it incredibly frustrating that every time I want to use the inspector, I need to turn on JavaScript, and then remember to turn it off again afterwards. I am also concerned that during the period it is turned on, sites in both the tab I'm inspecting and background tabs/windows might be able to execute scripts. What I would like is for the web inspector to have exclusive, guaranteed access to the JS engine when I right click on something and choose Inspect Element. This should be true regardless of whether it opens in a separate window or at the bottom of the website's window.
*** This bug has been marked as a duplicate of 12693 ***