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Second Monitor Display Scaling

sarahrb1989
sarahrb1989
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I am a Mac user and using a second monitor display. When I move a Firefox window to the second display it doubles in size. I cannot figure out how to get it to display properly (as it displays on my original monitor). Please help.

I am a Mac user and using a second monitor display. When I move a Firefox window to the second display it doubles in size. I cannot figure out how to get it to display properly (as it displays on my original monitor). Please help.
Attached screenshots

All Replies (4)

sarahrb1989
sarahrb1989 Question owner
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It is not that. All my other program windows are scaled correctly when I move them to the second display. It is only Firefox that is doing this.

sarahrb1989
sarahrb1989 Question owner
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I’ve already used the about:config to set the main display to 2. If I do it again once I’ve dragged the window over to the second display then it rescales on my main monitor too which I don’t want. I just want the window to be the same scale on BOTH monitors.

jonzn4SUSE
jonzn4SUSE
  • Top 10 Contributor
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I'm on a Macbook Pro from 2012 running 10.13.6 and here are my settings.

Displays: Color LCD: 

 Display Type:	Built-In Retina LCD
 Resolution:	2880 x 1800 Retina
 Framebuffer Depth:	24-Bit Color (ARGB8888)
 Main Display:	Yes
 Mirror:	Off
 Online:	Yes
 Rotation:	Supported
 Automatically Adjust Brightness:	No

HP Z27n: 

 Resolution:	2560 x 1440 (QHD/WQHD - Wide Quad High Definition)
 UI Looks like:	2560 x 1440 @ 59 Hz
 Framebuffer Depth:	24-Bit Color (ARGB8888)
 Display Serial Number:	CNK7240MFG  
 Mirror:	Off
 Online:	Yes
 Rotation:	Supported
 Automatically Adjust Brightness:	No


What are your settings on your external monitor?

Modified by jonzn4SUSE

sarahrb1989
sarahrb1989 Question owner
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Here are my settings, they are both set to the same resolution.