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Firefox 26.0 not working correctly with Mac OSX 10.9.1. Text jumps from one size to another spontaneously

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I have used firefox on Mac computers for years. I am now running Maverick Mac OSX 10.9.1 and have major problems with text sizing in windows and open windows suddenly changing size (much smaller) and jumping to the left hand side of my desktop. Apple do not support Firefox so I cannot get help from them and Mozilla are impossible to contact directly. Can someone please help with this problem?

I have used firefox on Mac computers for years. I am now running Maverick Mac OSX 10.9.1 and have major problems with text sizing in windows and open windows suddenly changing size (much smaller) and jumping to the left hand side of my desktop. Apple do not support Firefox so I cannot get help from them and Mozilla are impossible to contact directly. Can someone please help with this problem?

Chosen solution

You can check for problems caused by a corrupted localstore.rdf file.


Reset the page zoom on pages that cause problems.

  • View > Zoom > Reset (Ctrl+0 (zero); Command+0 on Mac)

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.
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Seçilmiş Həll

You can check for problems caused by a corrupted localstore.rdf file.


Reset the page zoom on pages that cause problems.

  • View > Zoom > Reset (Ctrl+0 (zero); Command+0 on Mac)

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.
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I have OSX 10.9.1 and Firefox 27.0.1 and have assorted problems on hotmail, facebook, citrix, linkedin, and others, pages do not open, photos show blank, pages open then go grey, links do not always show or do not work, this is 2nd cry for HELP!!! form Firefox. can I go back to another previous version? I have used Firefox for years, do not want to go to Safari. barefoottrkr@hotmail.com