> The solution is to use an Open Source browser
Seems to me the solution is to use 3rd party services that are not tied to the browser at all.
For example I manage passwords with 1Password, not Chrome's or any other browser's sync services. And I use bookmarking services like Pocket which aren't tied to any browser.
Using independent services made by companies that care about their reputation (and therefore the quality of their product) makes a lot more sense to me then putting all your eggs into a single browser basket.