I've already viewed this one here, and it doesn't appear to be the one I'm searching for. Back a while ago, I had stumbled upon a gnome extension that looked alike apple's spotlight search , yet it claimed to search for active window that were currently opened.

Unfortunately, I didn't install it then, and I'm desparately in need of that extension, and I was wondering if the community would be familiar with it. Please drop the link/name of the extension if you've been using it.