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

Error count in Firefox developer toolbar is high after upgrade to Quantum.

  • 2 replies
  • 2 have this problem
  • 1 view
  • Last reply by DGSJM

more options

After upgrade to Quantum (57), Firefox shows an error count of hundreds (or thousands) in the bottom-right corner of developer toolbar. This happens regardless of the site I'm visiting and even just opening the developer console generates a handful more errors. But I don't see any specifics about the errors listed in the console.

The constant presence of an error count makes development more difficult. Critical errors are more difficult to notice.

What's going on? Am I missing something? Thanks

After upgrade to Quantum (57), Firefox shows an error count of hundreds (or thousands) in the bottom-right corner of developer toolbar. This happens regardless of the site I'm visiting and even just opening the developer console generates a handful more errors. But I don't see any specifics about the errors listed in the console. The constant presence of an error count makes development more difficult. Critical errors are more difficult to notice. What's going on? Am I missing something? Thanks
Attached screenshots

Modified by DGSJM

All Replies (2)

more options

I can see this happening in my copy of Firefox as well. It looks like this is a known bug in Firefox (https://bugzilla.mozilla.org/show_bug.cgi?id=1228034 ), which happens whenever multi-process support is enabled. Multiproecess support was likely automatically enabled for you when you upgraded, which is why you're just seeing this bug now.

If you want, you can disable multi-process by opening about:config, clicking "I'll be careful", typing "browser.tabs.remote.autostart" in the searchbox, and double-clicking to change the value that appears to "false". However, this will make Firefox noticeably slower, and also a bit less secure, so I wouldn't recommend doing it. May I suggest using the console in the developer toolbox (Tools menu > Web Developer > Web console) instead?

more options

I tried changing the "autostart" value in "about:config". For me, the property that fixed the problem was "browser.tabs.remote.autostart.2". However, I certainly would prefer Firefox to be as fast and secure as it can be. Disabling multi-process support doesn't sound ideal, though it does stop the error count from going haywire.

Also, I do use the console in the developer toolbox. But I like how the toolbar alerts me to errors even if the console is not open. That way, I don't have to browse with the console always open.

Thanks for your quick reply and suggestions!