Was extremely useful, but as of early May longer seems to work at all.

Agree with other reviewers that say it crashes messenger randomly. The problem is it will try to send a message but I'll think it went through, and the other person never gets it. Frustrating!

It seemed to be working better before. I went on FB today, ( I rarely do) and it had clearly tracked me all along.

It's been good for Facebook and Instagram. Not perfect as FB still seems to find ways to be intrusive even with multiple privacy extensions. But all of sudden I can't login to Instagram with this extension turned on. If I turn it off and login and then turn the extension back on, it closes the tab. Literally impossible to have the extension on and login into Instagram...completely defeats the purpose.

je ne sais meme pas a quoi ca sert

I'm sorry, but this extension seems the reason why i asked to changed password, causing i can't login on multiple device that using facebook container

v2.3.9 breaks a number of sites including gog because it excessively messes with the is-hidden css class, even when unrelated to facebook.

Still injects its CSS into EVERY website (without an option to disable it for localhost for example) with a habit of casually breaking many sites and not fixing for months...

Has just started adding content_script.css to all pages, modifying their appearance.

Changing body font-size of all websites

I'm sure it does a great job, but for whatever reason it started overriding some websites' fonts to the browser's default font, even in websites with no links to Facebook. Hope they fix it

Works, but to pay with Paypal I have to switch it always off....and on again...

It works great, except for the part where it can potentially cause data loss (switching a tab to or from the Facebook Container, e.g. by visiting Facebook.com from a Google.com search, causes the tab's navigation history to be discarded)
Note: it doesn't break your history menu or anything; as long as you don't clear your history, you should be able to get back to where you were by digging through that. However, it's quite tedious and for some people, Multi-Account Containers might be a better choice.

Breaking too much of the site. Media doesn't load for the most part. I will just use Facebook in a virtual machine from here on in.

I love the spirit of this extension - but after extensive use, it appears to be the root cause of a number of frustrating Firefox issues in daily life: gmail (oops error 1) in persistent tab, loss of the ability to use search engines within the navigation bar (ie. searches stop executing), loss of website navigation in the navigation bar (cannot resolve DNS name, as if the GET method is interrupted).

Removing this extension resolves all of the above issues, I would be an avid user if it didn't come at the expense of FF stability.

it creates H1 to all pages with the phrase: "Facebook Container" should not interfere with the original page document outline at all. ???