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I use non fullscreen Firefox window - have to scroll horizontally. Can I spoof screen resolution information?

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  • 5 have this problem
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  • Last reply by cor-el

mlesmana
mlesmana
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Screen resolution information captured by Javascript shows the full monitor resolution. Meanwhile I don't maximize my Firefox (use Windows left and right snap). It seems to me that many websites use this info to decide how to render a page. Thus rendering wide pages that require me to scroll horizontally - even on https://support.mozilla.org/en-US/home

I have tried the FireSizer add on but it did not help. FireSizer only changes my browser windows size, websites (e.g. http://www.whatismyscreenresolution.com/) still reported my full screen resolution and not the browser windows size.

I know that I can use the zoom functionality, but that tends to render text too small for comfort.

Additional info: - monitor resolution: 1920x1200

Screen resolution information captured by Javascript shows the full monitor resolution. Meanwhile I don't maximize my Firefox (use Windows left and right snap). It seems to me that many websites use this info to decide how to render a page. Thus rendering wide pages that require me to scroll horizontally - even on https://support.mozilla.org/en-US/home I have tried the FireSizer add on but it did not help. FireSizer only changes my browser windows size, websites (e.g. http://www.whatismyscreenresolution.com/) still reported my full screen resolution and not the browser windows size. I know that I can use the zoom functionality, but that tends to render text too small for comfort. Additional info: - monitor resolution: 1920x1200

All Replies (1)

cor-el
cor-el
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  • Top 10 Contributor
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That depends which window and screen properties a website checks via JavaScript.

You can check out on the browserspy website how websites see your windows settings:

Copy and paste this code in the command line in the Web Console (Web Developer > Web Console; Ctrl+Shift+K) and press the Enter key. 

alert("Current Window: "+window.outerWidth+" x "+window.outerHeight+"\nScreen Available: "+screen.availWidth+" x "+screen.availHeight+"\nFull Screen Size: "+screen.width+" x "+screen.height+"\n\nwindow.outerWidth="+window.outerWidth+"\nwindow.outerHeight="+window.outerHeight+"\n\nwindow.innerWidth="+window.innerWidth+"\nwindow.innerHeight="+window.innerHeight);