How to disable middle-click clipboard URL loading in Firefox

It has always annoyed me that if I accidentally middle-click somewhere in Firefox, it tries to load whatever is in my clipboard as a URL.  Granted, I'm not one of the old-school Unix folks who actually uses middle-click to paste things normally, but that's always seemed crazy to me.  I mean, if I want to enter a URL, I click on the address bar, where URLs are normally entered, and not in the middle of the window.  Weird.

At any rate, go to "about:config" and set "middlemouse.contentLoadURL" to false, and this obnoxious behavior goes away.