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Cuireadh an snáithe seo sa chartlann. Cuir ceist nua má tá cabhair uait.

After opening Firefox, the webpage continuously changes size. How can I correct this? I've already uninstalled/installed it twice.

Kavanova
Kavanova
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I have windows 7 home (64 bit) on a sony vaio laptop. I have Firefox and IE installed. IE woks fine, but I prefer Firefox. Unfortunately, with no changes that I purposely installed, about a month ago, my Firefox started changing screen/font sizes. The entire page began changing sizes in font as frequently as every half-second to every 10 seconds. It would get bigger...then smaller...then even bigger, etc. It always seems to eventually settle in on a much larger size. Then I have to press "Control / 0" to bring it back to the normal size. Unfortunately, once I do that.... the whole process begins again.

I have Norton 360 installed and actively working. All protections are noted as up to date and "protected."

I've uninstalled Firefox twice now and reinstalled. The same issue happens. I'm not sure what is causing it or how to correct it. Any assistance would be greatly appreciated.

I have windows 7 home (64 bit) on a sony vaio laptop. I have Firefox and IE installed. IE woks fine, but I prefer Firefox. Unfortunately, with no changes that I purposely installed, about a month ago, my Firefox started changing screen/font sizes. The entire page began changing sizes in font as frequently as every half-second to every 10 seconds. It would get bigger...then smaller...then even bigger, etc. It always seems to eventually settle in on a much larger size. Then I have to press "Control / 0" to bring it back to the normal size. Unfortunately, once I do that.... the whole process begins again. I have Norton 360 installed and actively working. All protections are noted as up to date and "protected." I've uninstalled Firefox twice now and reinstalled. The same issue happens. I'm not sure what is causing it or how to correct it. Any assistance would be greatly appreciated.

All Replies (2)

Andrew
Andrew
  • Moderator
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Hello,

Firefox on Windows is now following display scaling options which may render text larger on high resolution displays. There's more than one way to resolve this problem. See the Webpages are large and blurry after updating Firefox - how to fix article for one suggestion. Here's another possible solution:

  • Type about:config into the Firefox address bar and tap on the Enter key.
  • If the warning This might void your warranty appears, click I'll be careful, I promise.
  • Search for layout.css.devPixelsPerPx

Fx22layout.css.devPixelsPerPx

  • Double-click on layout.css.devPixelsPerPx to modify its value. The default is -1.0 in Firefox 22 and above. Change it to 1.0 to make it work like in previous Firefox versions.

If necessary, further adjust the value in 0.1 or 0.05 steps. Use values between 1.0 and about 0.5 to reduce elements in size. Use values greater than 1.0 to increase size. For example, a value of 1.25 will increase font size to 125% to accommodate the default DPI setting in Windows 8. Double check the value that you enter. Setting a too small value will make everything disappear and a too large value will blow things up.

If web pages still need to be adjusted then you can look at the Default FullZoom Level or NoSquint extension.

To adjust the font size for the user interface, you can use the Theme Font & Size Changer extension.

Did this fix your problems? Please report back to us!

Thank you.

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 10 Contributor
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As you probably know, Firefox will zoom the page if you hold the Ctrl key and scroll the mouse wheel. Sometimes for unknown reasons Firefox will get a bit confused with fancier input devices and nonstandard drivers.

If you have a wireless mouse or a multi-button track ball, could you test with a basic wired mouse?

Another way to investigate this theory is to change the behavior of Ctrl+wheel. Here's how:

(1) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(2) In the search box that appears above the list, type or paste wheel and pause while the list is filtered

(3) Double-click the mousewheel.with_control.action preference and enter the desired value:

  • 0 => scroll by lines
  • 1 => scroll by pages
  • 2 => previous / next page
  • 3 => zoom (default)
  • 4 => scroll by pixels