Deprecated: This extension is not compatible with recent versions of Firefox, and since the menu is changing soon and WebExtensions are coming, I do not plan to update it. (I'd push an update if someone sends a patch, of course.)
Keep the menu panel tidy by leaving tools you almost never use out. When you need one "just this once", it's available under the More Tools button. The rest of the time, those unloved tools are left in the customizing palette, waiting for you to change your mind.