I did try that, but found that it still remembered site info for accounts I was logged in until fully I closed everything related to the firefox browser. So containers has been easiest solution except for the process of manually creating and then deleting ones I didn't need anymore beyond the one session.
I had used Temporary Containers, but it hasn't been updated since February 8, 2021. Not actively monitored for security by Mozilla either so stopped using it. That addon was a perfect experience though for what I wanted.
@ImaginaryFox I see. That's reasonable. I also had Temporary Containers in my head, but didn't suggest it as you wanted a native solution. Didn't even notice how old last update was! Unfortunately from my view and additional research, could not find a solution for you. It would be nice to have a "Open in New Temporary Container for Tab", that is managed temporarily and automatically deleted after closing tab.
I had used Temporary Containers, but it hasn't been updated since February 8, 2021. Not actively monitored for security by Mozilla either so stopped using it. That addon was a perfect experience though for what I wanted.
Code doesn't rot, so you can use the extension. Is it not fit for purpose? Are you aware of any security issues? What is the scope of impact if there IS an issue?
Code DOES rot, because the dependency you rely on stop being updated, oh btw this thing has a critical cve now, this isn’t supported by the new addon API, …