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accessibility. The default size of web pages on firefox on a 17" macbook pro is unreadable. Not related to font size. Needs constant zooming. No way to chang


I wanted to enter the forum to ask about accessibility features for dyslexia with Firefox. The default webpage setting for firefox on my 17" macbook pro is tiny and takes up only the very central part of the screen. I can read a normal average well presented and spaced webpage font perfectly well, but to read something squashed down in size into the centre of a widescreen display is impossible. None of the firefox or mac menus appear to give any options to change the default size of the web page display. Pages can be zoomed in on, but that has to be done for every page every time and takes quite a number of "Apple key" +'s to get it to just a normal full screen size to show the font it the normal size it should be in and nut shrunk. Accessibility questions advise to increase font size, but that makes no difference at all. If there is a problem with firefox not displaying accessibly on a mac please can it be fixed by firefox or apple or an option built in to go to real full screen instead of the full screen setting leaving the page in its pretend squashed up "fullscreen". also if there is a solution, please could the help menus on the mac and in firefox and in the interactive questions before reaching this stage on this site advise the solution. saying just to zoom in is exhausting for every page every time and saying to increase font size for accessibility is just upsetting when the page stays so small, so even the largest fonts appear less than font size 10. please can there be a built in way and a built in guidance route to change the default page display size. thank you. not just for me but in the interests of accessibility for everyone using firefox on a mac. since starting this i did find something that led me to a downloadable firefox zoom add on, but I have continued with my question because I ask that other could be guided to this as standard please through accessibilty and display questions. Could there please perhaps be as standard an option in the view menu under "zoom" to increase default zoom setting. thank you.

Additional System Details

Installed Plug-ins

  • Shockwave Flash 11.6 r602
  • Microsoft Office for Mac SharePoint Browser Plug-in
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in web pages. For more information, visit the QuickTime Web site.
  • Displays Java applet content, or a placeholder if Java is not installed.


  • User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:19.0) Gecko/20100101 Firefox/19.0

More Information

  • Top 10 Contributor
2357 solutions 20872 answers

Helpful Reply

Paragraph breaks are good for readability. ;-)

Have you noticed any difference between your MacBook and others at the Apple store? Wondering whether this is a configurable setting at the system level, i.e., DPI.

You can default Firefox to a larger zoom level to avoid having to zoom every page. You'll still be able to adjust the size for individual sites as needed. It sounds as though you are aware of these add-ons:

There are some discussions about changing coming in Firefox 22 (I think) to address higher density displays like the Retina display. So perhaps there will be a built-in setting to address this in the future.

  • Top 10 Contributor
  • Moderator
10749 solutions 96724 answers

Use this extension to adjust the font size for the user interface:

Increase the String pref layout.css.devPixelsPerPx from 1.0 to 2.0 in 0.1 or 0.05 steps to adjust the size of all fonts and other elements in Firefox.
The layout.css.devPixelsPerPx pref is a String value parsed to a float and allows to fine tune the dimensions of all elements (user interface and web pages) more precisely (resolution 0.1 or 0.05).
You can use values between 0.05 and 1.0 to reduce elements in size or use values greater than 1.0 to magnify and make elements larger (percentage divided by DPI, % / DPI).