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Mozilla Firefox 55 is running slow on Mac OS X 10.9

  • 2 respostas
  • 1 has this problem
  • 6 views
  • Last reply by cor-el

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Installed Mozilla 55 on Mac OS X 10.9 and the pages are loading slow . It takes about 2 or 3 minutes to load a page . need a solution for this issue .

Installed Mozilla 55 on Mac OS X 10.9 and the pages are loading slow . It takes about 2 or 3 minutes to load a page . need a solution for this issue .

All Replies (2)

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Any reason you are sticking with Mac 10.9? It's old, insecure and unsupported by Apple.

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

  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Appearance
  • do NOT click the "Refresh Firefox" button on the Safe Mode start window

You can try to modify multi-process settings to see if this has effect.

  • set dom.ipc.processCount to 1 if it is currently set to a higher value (4)
  • disable multi-process windows in Firefox

You can disable multi-process windows in Firefox by setting these prefs to false on the about:config page.

  • browser.tabs.remote.autostart = false
  • browser.tabs.remote.autostart.2 = false

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.


Try to disable IPv6 (check for other possible causes as well).

cor-el modificouno o