I'd like to block a specific element on a website, everytime I go on it, and I wanna do it for any element on a given webpage when I want to it. Moreover, I want to space freed by the deleted element be used to display more of the website's content.
For instance, say I want to hide the sidebar on Stackoverflow (id = "sidebar") and let the content (id = "content") automatically fill the freed space on its right side (by centering itself for exemple).
I could also want to make an ad banner on a website be bloked and the space used to let the website display more content
I've been searching AdBlock, NoScript and Ghostery extensions, they block and fill up spaces liberated by all the "Facebook Like" "Google +1" etc. But I can't tell them to specifically block a one given element and let another element take its freed place to extend itself.
If this is possible, how can I achieve it ?
I accept Google Chrome answers too, even if I'm looking for firefox ones preferably I accept "partial" solutions, such as only blocking a given element and not letting the others take the freed space (which I think might be impossible).