These types of answers are unacceptable as "Help", just sayin. "I'm wondering WHY you want to use magnet links for (besides the obvious reason of torrenting)." The reason why someone would want to do something isn't of your concern, really. However, WHY someone would want to set a particular application of launching magnet links, without having to search on help forums to find something hidden in about:config is because not everyone wants to install a list of 3rd party programs to a Windows installation. Nor CAN everybody install such things. So what some people do is use "Portable Apps." When this is done, firefox isn't going to become aware that this type of program CAN be used on the Windows install in question, because it's not actually installed. Why is there not an "Add" option for the "Applications" list in the settings panel? That makes no sense. Essentially what's been done here is that Firefox says "I'll only interface with programs that are fully installed on this machine, and to hell with your portable apps." I realize that there is a growing trend of adding bumpers and safety pads to everything in the world, but people really can take care of themselves. I also realize that there has been this trend where FireFox devs have been taking what users actually like/want and ignoring it. Which is unfortunate. I'm not actually going to come back here and read anything said back to me. I've already used the hidden method of fixing my problem. My reason for typing this is that I think there should be an ability to add app associations to that list. network.protocol-handler.expose.magnet bool == true