Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Firefox 57.0.4 on macOS doesn't warn on quit

  • 1 reply
  • 12 have this problem
  • 5 views
  • Last reply by cor-el

more options

Running Firefox 57.0.4 on macOS 10.12.6 (Sierra). I have the following in about:config set to "true": browser.tabs.warnOnClose browser.tabs.warnOnCloseOtherTabs browser.tabs.warnOnOpen browser.warnOnQuit browser.showQuitWarning

Some resources online mention setting warnOnRestart to "true," but there is no such option. When I quit with CMD+Q or through the Firefox menu, there is no warning before quitting and Firefox just quits even when I have multiple tabs open. I have restarted both Firefox and my Macbook after changing these settings. I would appreciate if anyone knows of a way to get Firefox 57 on macOS to warn before quitting.

Thanks for your help!

Running Firefox 57.0.4 on macOS 10.12.6 (Sierra). I have the following in about:config set to "true": browser.tabs.warnOnClose browser.tabs.warnOnCloseOtherTabs browser.tabs.warnOnOpen browser.warnOnQuit browser.showQuitWarning Some resources online mention setting warnOnRestart to "true," but there is no such option. When I quit with CMD+Q or through the Firefox menu, there is no warning before quitting and Firefox just quits even when I have multiple tabs open. I have restarted both Firefox and my Macbook after changing these settings. I would appreciate if anyone knows of a way to get Firefox 57 on macOS to warn before quitting. Thanks for your help!

Chosen solution

Are you reopening tabs automatically on the next start?

  • "Show my windows and tabs from last time"

If that is the case then Firefox wont show a warning.


There are other things that need attention.

The System Details list shows an outdated Flash plugin.

  • Shockwave Flash 23.0 r0

You can download the latest Flash player plugin for Firefox on this page. See "Still having problems".n*http://helpx.adobe.com/flash-player/kb/installation-problems-flash-player-windows.html

Read this answer in context 👍 1

All Replies (1)

more options

Chosen Solution

Are you reopening tabs automatically on the next start?

  • "Show my windows and tabs from last time"

If that is the case then Firefox wont show a warning.


There are other things that need attention.

The System Details list shows an outdated Flash plugin.

  • Shockwave Flash 23.0 r0

You can download the latest Flash player plugin for Firefox on this page. See "Still having problems".n*http://helpx.adobe.com/flash-player/kb/installation-problems-flash-player-windows.html