That’d certainly prevent most tracking, yeah. This new Firefox feature should make #2 and #3 unnecessary.

I think this feature by Firefox is great, and privacy options are getting objectively better, if slowly. But the cynic in me guessing that server side tracking methods are going to start getting secretly better, if they haven’t already.

The solution is political action. You're describing a workaround that only a few of the most concerned people will be willing to use.

To reduce the burden use extension Temporary containers, so each tab opens into a clean environment.

And use Firefox container to auto-open domains on specific containers where you want to keep sessions or have a shared profile among various domains

How about just using the "Delete Cookies" -feature of the browser? And maybe there's a plugin that would make that one-click process?

I'd replace 3 with self-destructing cookies.

I just by default use private mode. Pretty sure in Safari that helps.

2 and 3 are "browse in private mode", to make thing simple.