I would have the same question if I didn't see the response come back from https://normandy.cdn.mozilla.net/ myself.

I encourage you to go through the whole Normandy process yourself in a test environment, and even better (if possible), check out the code to see whether it looks legit or benign.

I'm happy, because I went through and checked it out myself without needing to enable Normandy on my actual Firefox, but ultimately, it will be great when Moz can get instructions for manually applying the fix out.