Firefox has been integrated with the spyware platform called "Google Analytics"（Issues · mozilla/addons-frontend · GitHub). Firefox has been confirmed to now send analytics to Google. According to a Firefox developer the spyware in Firefox is "extremely useful to us and we have already weighed the cost/benefit of using tracking." and that Firefox will not remove Google Analytics support entirely. Firefox's position on privacy is made very clear with this quote:
"Wanted to address your position though: We don't give the "data directly to Google". See the discussion here: 858839 - Do Not Track is not respected on Mozilla Websites. The short version is: tl;dr: We now have an option to opt-out of Google doing anything with the data that Google Analytics collections on Mozilla websites. GA tracking is anonymous and at the aggregate level and we use it to improve the experience of our websites. We are collecting aggregate and non-identifiable data in numbers to ensure our development/UX changes are met well. We can respect privacy and still have analytics; in fact Mozilla's aim is for an experience that values user privacy and usability (I'd say Apple also wants UX that fits that mold, as an example). We need some data, anonymized and aggregated, to do this. "
The best takeaway to this is that Mozilla wants to pretend that including spyware in their program is somehow not a breach of privacy, and that Firefox could possibly be respecting user privacy while simultaneously collecting data on users and sending it to Google. It's strongly suggested reading the GitHub thread and the further anti-privacy statements the Mozilla employee makes while defending the spyware features in Firefox. It's very dangerous to assert that there is somehow a middle ground between respecting user privacy and datamining the user.
startpage据说已被广告公司收购，我并没有核实，但我遇到过多次要填验证码的情况，我对其是否真正欢迎隐私表示怀疑。
proton可能是广告打得最好的，你到处都能看到各种隐私教程里对它的吹捧，然而它有些非常明显的问题：E-mail providers - which one to choose?
tutanota看似隐私政策很好，不保存ip，但如果你用了vpn或tor，照样保存
Storage only takes place for IP addresses made anonymous which are therefore not personal data any more
你的信用卡数据也被分享
For the execution of credit card payments your credit card data will be shared with our payment service provider Braintree. This includes the transfer of personal data into a third country (USA)
