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You can block shadow profiling with a combination of something like ublock origin with the right lists and cookie autodelete...

But it is much harder to avoid that someone that has your number, places it his contacts lists and then gets uploaded. At least without goverment intervention... you can do it with burner phone numbers too... but still a bit hard.

https://www.eff.org/deeplinks/2018/09/you-gave-facebook-your-number-security-they-used-it-ads