Spoofing user agents will sort of defeat UA-based tracking, but so will using the stock UA for the most common version of your browser. I think it would make mo

Spoofing user agents will sort of defeat UA-based tracking, but so will using the stock UA for the most common version of your browser. I think it would make more sense to find the most common Firefox UA and switch to that. Probably something like this: "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:39.0) Gecko/20100101 Firefox/39.0". The advantage here is that you aren't likely to run across weird behavior from sites that sniff UA to determine feature set. That's clearly gross behavior, but it's also necessary. For instance, there's no way to determine if a browser supports JPEG2000 other than to sniff the UA for Safari -- it doesn't send an appropriate Accept header. Likewise for many other situations.