Earlier quoted context omitted.
AFAIK they do the opposite: They've pioneered ways to target advertising without your data leaving your computer. See for example, https://www.adexchanger.com/privacy/mozilla-acquires-anonym-... "That shared mission is predicated on the notion that advertising and privacy are not – or at least don’t have to be – mutually exclusive." And it goes into detail on the investment and technology in that area.
If they've pioneered such technologies, they aren't using them. Their Privacy Notice enumerates many types of data that Mozilla collects and passes along to "partners"/advertisers. For example: > Mozilla collects technical and interaction data, such as the position, size, views and clicks on New Tab content or ads, to understand how people are interacting with our content and to personalize future content, including…
It's meaningless data to you: It doesn't say what you click on, just where and how big the ads are, and how many times you click. It doesn't identify you or reveal anything about you, except that you clicked on some unknown ads.
> It's also silly to suggest that targeting advertising without tracking users needs to be "pioneered". It's obvious that Mozilla could have the browser download this month's list of sponsored search keywords and have the browser check search strings against that list, without going off-device.
These are the words of someone who hasn't done it. Look at the article; what advertisers want and what the privacy-destroying competition does is much more sophisticated than what you describe. For example,
Anonym also has technology that allows ad platforms and advertisers to securely share encrypted impression and conversion data within a trusted execution environment for attribution, causal lift measurement and lookalike modeling. (A trusted execution environment is the secure area of a main processor where code can be run safely and in isolation.)
To be fair, the major ad platforms have long offered attribution and measurement solutions, Mudd said. “But they required the data to come into their system,” he added. “In this world, that doesn’t have to happen.”