Extension forces all Facebook tabs to load at startup, completely exhausing all memory

[jakejgw]

• Facebook Container Version: 2.1.2
• Operating System + Version: Linux 5.10, Manjaro XFCE 4.14
• Firefox Version: 84.0.2 64bit
• Other installed Add-ons + Version + Enabled/Disabled-Status: Issue occurs when Facebook Container is the only enabled extension. Many disabled extensions, too many to list.

Actual behavior

Firefox starts up and restores three windows containing hundreds of tabs, including many (~100?) Facebook tabs. Firefox is set to restore tabs on startup, and is set not to load tabs until requested. Firefox stalls while Facebook Container extension apparently loads every single Facebook tab. The entire system eventually stalls when all 8GB physical memory and 5GB swap are completely exhausted.

Expected behavior

Firefox starts up and restores all previously open tabs. Only the single focused tab in each of the three open windows is loaded. Facebook tabs do not load until requested.

Steps to reproduce

1. Quit Firefox (or kill process if needed).
2. Restart Firefox.

[natelovesyou]

I was looking for information on why Firefox was getting bogged down and even crashing when trying to resume because most or all Facebook tabs were being opened on session restore. It's maddening how long it takes Firefox to start up because of it. I'm glad to find out it was the fault of an extension, but hopefully it's fixed soon. I may have to disable the culprit until then.

[natelovesyou]

Steps to reproduce:

1. Install Facebook Container (2.1.2) on Firefox (using Nightly 86.0a1 (2021-01-17) 64-bit).
2. Open Facebook in multiple tabs.
3. Close Firefox.
4. Open Firefox and resume the last session (if not set to automatically resume).
5. Observe that all of the Facebook tabs load, and only the Facebook tabs. All other sites remain unloaded.

[jakejgw]

Workaround: Don't use this extension at all; instead use Firefox Multi-Account Containers. It requires some setup:

• First, if you don't already have a "Facebook" container, create it. I didn't have to do this because I had already been using the Facebook Container extension, but I'm assuming that if you create any arbitrary container manually that you intend to use for Facebook, it will work.
• Open a new tab and load Facebook in it (you do not have to log in yet).
• Bring up the context menu (right-click) on the tab (the actual tab UI element at the very top in the tab bar) you've just loaded Facebook in, and choose Reopen in Container -> Facebook (or whatever container you're going to use for this).
• Once you've got the page loaded in the container, bring up the context menu (right-click) in the body of the page you're looking at, and choose Firefox Multi-Account Containers -> Always Open in This Container.
• That's it! It takes some more setup, but it works, and it doesn't cause all of your Facebook tabs to load when you open your browser!
• Someone correct me if I've missed something or if the Facebook Container extension somehow provides more "containing" of Facebook than I'm indicating here. I don't want to lead anyone to assume that it's exactly equivalent if it's not!

• Edit/Update: From this extension's readme:

  When you first install the add-on, it signs you out of Facebook and deletes the cookies that Facebook uses to track you on other websites.

  So it looks like if you want exactly the same thing that this extension does, you'll have to make sure you're signed out of Facebook in your non-container and non-Facebook container tabs and also delete all your Facebook cookies.

[maxxcrawford]

@jakejgw @natelovesyou I walked through the steps and can confirm the issue. It looks like it only applies to facebook.com domains? (I had messenger.com open in a tab as well and it wouldn't reload on start-up).

We'll look into this.

cc/ @groovecoder

[maxxcrawford]

Looks like this function may be the culprit.

In this function, we comments for the following bugs:

• https://github.com/mozilla/multi-account-containers/issues/474
• https://bugzilla.mozilla.org/show_bug.cgi?id=1447551

[mohmyo]

I dropped using Facebook Container 2 weeks ago because of this issue, it was also eating up ram so badly. I'm using windows 10 latest version, both FB container and FF on the latest version too.