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Firefox intermittently stops working for short (45 seconds) periods of time

  • 3 replies
  • 1 has this problem
  • 6 views
  • Last reply by cor-el

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In general Firefox works well for me. However, when I first open a new browser window it will work for about 20 seconds. I then get a period of ~45-60 seconds during which no websites can be displayed. I get the message "Server not found”. This happens regardless if I am at work or home on the wireless networks, and does not occur in google chrome.

After about 60 seconds of periodic refreshing, the website will load and Firefox works fine again. Then, after about 20 minutes, any new pages i try to open will give me the same problem for another period of about 45-60 seconds

In general Firefox works well for me. However, when I first open a new browser window it will work for about 20 seconds. I then get a period of ~45-60 seconds during which no websites can be displayed. I get the message "Server not found”. This happens regardless if I am at work or home on the wireless networks, and does not occur in google chrome. After about 60 seconds of periodic refreshing, the website will load and Firefox works fine again. Then, after about 20 minutes, any new pages i try to open will give me the same problem for another period of about 45-60 seconds

All Replies (3)

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You appear to have the "Mozilla Safe Browsing 2.0.14" extension that is considered malware.

  • bug 799266 - Blocklist malicious "Mozilla Safe Browsing" add-on

(please do not comment in bug reports: https://bugzilla.mozilla.org/page.cgi?id=etiquette.html)

Modified by cor-el

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Thank you for the help.

I followed all the links and I have appeared to have removed the Safe Browsing extension.

However, the problem I originally reported is still persisting.

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Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).

  • Do NOT click the Reset button on the Safe mode start window or otherwise make changes.

Try to boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.

A possible cause is security software (firewall,anti-virus) that blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.

Remove all rules for Firefox and the plugin-container from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox and the plugin-container process and the updater process.

See: