"File -> Work Offline" should get a checkmark when offline mode is active. Doesn't that work for?

Is that check mark box missing for other menu items as well where this applies like various settings in the View menu ?

Start Firefox in Troubleshoot Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration or if userChrome.css/userContent.css is causing the problem.

• switch to the Default System theme: "3-bar" menu button or Tools -> Add-ons -> Themes
• do NOT click the "Refresh Firefox" button on the Troubleshoot Mode start window

• https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode
• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

Thank you very much. There is no check mark. I will try all your suggestions and get back to you tomorrow. Again, not having emails is much more difficult that I ever thought.

No email; big problem. I must be online but cannot download my messages.

I get the feeling that you are actually referring to the Thunderbird email client and not the (desktop) Firefox web browser.

Yes, it's Thunderbird staying in offline mode and I can't get to online, although some email get through and all of the internet is OK.

This is what I discovered:

FIREBOX "Work Offline" clicking turns on the check mark but also turns it off. No change. THUNDERBIRD "offline" same as above; no change.

Troubleshoot Mode on shows the following: "ALL MAIL" doesn't show all (11032 emails). But IMPORTANT shows (3400) and I see everything. Turning office this mode doesn't change any display. Even if it is off I see the screen without all the normal stuff.

When an email arrives, I get the notification but not all emails, just some.

Bottom line I cannot turn off OFFLINE!

I just got a notification and see the email. How do I get back to the normal display?

Well it sorta working. Please help with the following: 1) How to get to the original display? 2) Still in offline mode; Back to online? 3) Why ALL MAIL does have all mail, but IMPORTANT does?

Thank you very much.

P.S. My backup was to go directly to Gmail.

Fixed # 1

On #3: AllMail folder and Important folder are managed by Gmail, not by the user. Few users need them, they have a huge impact on disk storage, and slow thunderbird. If you don't use them, you can unsubscribe from them.

Thank you for this insight. For years I have never looked at Gmail so I have no idea how it was setup. I will investigate.

Can you help with the offline issue?

no. if work offline is not checked, you should be online. If you are receiving mail, then you are online. Your comments have me confused.

Yes, when this happened (no emails) I through this was my problem. But I always could use the internet. And Thunderbird always announced the arrival of an email. And I always used ALL MAIL. And the ALL MAIL stopped. Your suggestion will require a deep dive in GMAIL.

Thank you Mozilla and you Davis for your help pointing me in the right direction.