1979907 - Firefox Nightly logs out of Firefox account on every restart

Status: UNCONFIRMED

(Firefox :: Firefox Accounts, defect, P3)

Description

[Vedant]

In recent Nightly builds, Firefox keeps logging me out of my Firefox account (top-right corner), requiring me to sign in again after every restart.
This makes syncing settings and extensions unreliable.

Steps to Reproduce:

1. Sign in to Firefox account in Nightly
2. Close the browser
3. Reopen the browser

Expected Result:
Stay signed in to the Firefox account across restarts

Actual Result:
Firefox shows I'm signed out and asks me to sign in again

Reproducible:
Every time

Troubleshooting Attempted:
Tried with a fresh Nightly profile
No extensions interfering
No "clear data on close" setting enabled
Confirmed system clock is correct

Nightly Version:
143.0a1

Platform:
Windows 10 (x64)

Comment 1

[Ardelean Oana, Desktop Test Engineering [:oardelean]]

Hello Vedant, thank you for the bug report!
Unfortunately I could not reproduce the issue. I had logged into Firefox Nightly with an Fx account, but after closing and re-opening the browser, the account was still logged on. There is a slight glitch that might show the user is logged out of the account, but all functionalities are restored almost immediately and the account is still connected and functional.

Would you be so kind as to answer a few questions so we can investigate this further?

• Could you please attach a copy of about:support here in the bug of the affected profile?
• Are there any other configurations needed to be setup in order to be able to reproduce this issue?

Thank you.

Comment 2

[Vedant]

Attachment: about support

Comment 3

[Vedant]

Thanks for your response. Please find my follow-up and the requested information below:

1. I’ve attached the output of about:support from the affected Firefox Nightly profile.

2. Firefox Account Logout Issue:

   • I am consistently logged out of my Firefox account (visible in the top-right corner) every time I close and reopen Firefox Nightly.
   • This started happening after a recent Nightly update about 3–4 days ago.
   • I’ve disabled “Delete cookies and site data when Firefox is closed.”
   • I'm not using private browsing or containers.
   • Sync settings are enabled for bookmarks, tabs, passwords, etc.
   • However, after each restart, I must manually sign in again, and Firefox Sync does not work until I do so.
   • This issue persists even with Norton Safe Web turned off, and even on a fresh profile.

3. Additional Issue – Norton 360 Conflict (Possibly Related):

   • I’m using Norton 360, and when Safe Web is enabled, Instagram fails to load in Firefox Nightly.
   • The page remains blank, and more severely, internet access on the PC becomes unstable, even though the connection remains technically active.
   • This behavior is exclusive to Firefox Nightly; other browsers like Chrome and Edge do not exhibit this issue.
   • Disabling Safe Web restores functionality for Instagram and stabilizes the internet connection.

Comment 4

[Mark Hammond [:markh] [:mhammond]]

It would be very interesting to see the "browser console" (https://firefox-source-docs.mozilla.org/devtools-user/browser_console/index.html) output after starting up Firefox - this might have relevant information about the problem.

Additional Issue – Norton 360 Conflict (Possibly Related):

It might be worth trying to rule this out first - these kinds of tools cause quite a number of problems in my experience. Sadly, it's possible that even with their addon disabled it might be injecting itself into Firefox, which always ends in tears for someone or other.

Comment 5

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:markh, could you have a look please?

For more information, please visit BugBot documentation.

Comment 6

[Vedant]

Summary:
Firefox Nightly logs out of Firefox Account after restart — session cookie deleted on shutdown

Steps to Reproduce:
Launch Firefox Nightly (tested with <insert exact build ID>).
Sign in to Firefox Account.
Close Nightly completely.
Reopen Nightly — account is logged out.

Actual Results:
Browser Console & MOZ_LOG show accounts.firefox.com session cookie is deleted at shutdown (CookieService::RemoveAll entry in logs).
No indication of remote sync/auth failure — this appears to be local cookie storage clearance.

Expected Results:
Session cookie for accounts.firefox.com should persist across restarts unless explicitly cleared via UI.

Additional Info:
Tested with new profile, all extensions disabled.
Delete cookies and site data when Firefox is closed is set to off.
Issue persists across builds.

Full log excerpt:
[2025-08-13 21:45:08.214] CookieService::RemoveAll called for base domain accounts.firefox.com
[2025-08-13 21:45:08.215] Removed session cookie: sessionToken from accounts.firefox.com
[2025-08-13 21:45:08.215] CookieService::RemoveAll completed
[2025-08-13 21:45:09.342] Startup: Auth token missing for accounts.firefox.com — triggering sign-in

Comment 7

[Mark Hammond [:markh] [:mhammond]]

I don't think the session cookie is involved here - deleting that just means you will not be logged in if you visit accounts.firefox.com in a tab, but should not kick out a connected sync session.