Well normally you wouldn't want one browser extension to interfere with another extension. However, there are contexts where that is very beneficial. Take a se

Well normally you wouldn't want one browser extension to interfere with another extension. However, there are contexts where that is very beneficial. Take a security or privacy extension which correctly identifies a harmful resource load. It doesn't matter whether that resource is being loaded in a content tab, loaded by another extension behind the scenes, or is local vs remote. It it still a harmful load. So a protective extension should be able to detect it, then inform the user and/or perform an appropriate blocking action. This, like some other special powers, is something that the user should have to explicitly grant to an extension via permissions interface.