[MaxBarraclough]

To mirror fsflover's comment:

> Does he go through every single line of code on every single application he uses to ensure privacy? Does this mean he is an expert in the Linux kernel? And chromium, and sendmail...

You're misunderstanding it. You don't need to go over every line to benefit from the source being available. It's very rare for bad actors to publish outright malicious source code and just hope no one spots it. People who want to release malware just about always insist that you cannot inspect the source code.

Of course, it's possible to release good source code and also introduce malware into the official binaries, lying about it corresponding to the published source, but that's another matter.

> It's just not feasible to have 100% confidence that third party software is ensuring your privacy.

It's rare to aim for absolute perfection and absolute guaranteed trustworthiness. Insisting on Free and Open Source software is a pretty effective means of avoiding many forms of malware.

[fsflover]

> Of course, it's possible to release good source-code and also introduce malware into the official binaries

Which is solved by reproducible builds.

[MaxBarraclough]

Right, or source-based distribution of packages.