WetGeek Firefox even lets users deny sending anonymous technical innformation to Mozilla.
Yes, and that is a good thing, but notice exactly what "technical and interaction data" consists of:
Interaction data: Firefox sends data about your interactions with Firefox to us (such as number of open tabs and windows; number of webpages visited; number and type of installed Firefox Add-ons; and session length) and Firefox features offered by Mozilla or our partners (such as interaction with Firefox search features and search partner referrals).
Technical data: Firefox sends data about your Firefox version and language; device operating system and hardware configuration; memory, basic information about crashes and errors; outcome of automated processes like updates, safebrowsing, and activation to us. When Firefox sends data to us, your IP address is temporarily collected as part of our server logs.
If you read the descriptions carefully, I think you will notice that Firefox continues to "call home" for syncing, updates, account management and other purposes even if those transmissions are disabled.
To get a feel for what Firefox collects, scroll down the document I linked and click open the "+" tags as you scroll down. I don't think that you'll be surprised, as experienced as you are in things technical, but Firefox transmits a boatload of data back and forth, depending on how you use the browser.
As a user, you can shut a lot of it down by not syncing and so on, but at some point the browser loses core functionality for users like me who have Firefox installed on multiple devices if it is shut down too far.
Don't get me wrong: I've used Firefox for close to 20 years now, and until the last few years, I used Firefox exclusively. During the last two years, I've also used Microsoft Edge. I think that Firefox is a outstanding browser, and I have it installed on all of my devices (3 desktops, 3 laptops, an Android tablet and my iPhone). I use it daily. But Firefox, good as it is, transmits a lot of data back and forth the way I use it, even though I've taken reasonable steps to limit the amount of data transmitted. Microsoft Edge does, too. I think that is the way of the world in our online, interconnected technology environment.
