I'm about 98% sure that extensions have nothing to do with browser fingerprinting. Everything I've seen indicates plugins do but extensions don't. So this wouldn't (unless I'm wrong) make a difference. And if it did, anybody that's enough of a power user to be using Adguard or uBO would likely be running other extensions for security and privacy, and then using those and not an ad blocker would only make them stand out from the crowd even more. I've come to the conclusion trying to resist fingerprinting is nearly pointless, since there are so many factors and it's hard to control all of them, and even if you do it's hard to make yourself not unique enough you can still be identified. Firefox's privacy.resistFingerprinting preference is the best bet, but it's also not perfect, and I personally don't use it (yet). If you really want to maintain anonymity, a VPN and/or Tor (TBB) are your only real options, and a VM can help some as well, though it only serves to anonymize your computer, not your connection. So it depends what your threat level is and how much you need privacy.