Firefox's anti-tracking protection doesn't block google analytics by default. They only block "third party" cookies - which in practice translates as: Google's competition.
The fox knows better than to bite the hand that feeds it.
Firefox docs and disconnect don't say anything about this
https://support.mozilla.org/en-US/kb/enhanced-tracking-prote...
The above specifically shows you to make sure your site continues to function when Google Analytics is blocked by Firefox. I can't find any evidence that Firefox doesn't block Google Analytics.
"Cookie blocking" and GDPR is just Google abusing its monopoly position, nothing more.
Source: I work in adtech.
-- For customers that are using Google Analytics' Display Advertiser features, such as remarketing, a third-party DoubleClick cookie is used in addition to the other cookies described in this document for just these features. For more information about this cookie, visit the Google Advertising Privacy FAQ.
Source: https://developers.google.com/analytics/devguides/collection...