I just downloaded Fiddler, and when I tried to edit the rules, it asked me if I would like to download the syntax editor. I did so, installed it, and it told me it would be available next time I started Fiddler.
I restarted, but when I tried to edit the rules, I got the same message asking if I wanted to download the editor. As I'd already installed it, I said no, at which point it opened the file in Notepad.
How do I get it to use the editor? I know this is installed, as I can start it manually, I want it to be used from within Fiddler.