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when LCD is turn off, firefox boot up in a much bigger size

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I have firefox as part of my startup in windows 7. I have this for years. My screen is a UHD 40" running at 3840x2160

Normally, I'll turn on the PC, then after the PC is boot up, I'll then walk to the other side of my desk and turn on the monitor.

In the past few months, when I turn on my monitor, firefox takes up way bigger than 3840x2160. It should have take up only 1280x2160. So I have to re-size it.

But this ONLY happens when my screen is turn off when I boot up. If my LCD is turn ON just when my PC is turning on, after the PC is fully boot up, firefox will load up automatically, and it will then load up with the proper screen size

I have firefox as part of my startup in windows 7. I have this for years. My screen is a UHD 40" running at 3840x2160 Normally, I'll turn on the PC, then after the PC is boot up, I'll then walk to the other side of my desk and turn on the monitor. In the past few months, when I turn on my monitor, firefox takes up way bigger than 3840x2160. It should have take up only 1280x2160. So I have to re-size it. But this ONLY happens when my screen is turn off when I boot up. If my LCD is turn ON just when my PC is turning on, after the PC is fully boot up, firefox will load up automatically, and it will then load up with the proper screen size

All Replies (3)

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So, turn on the monitor first. (Grin)

I'd guess there was a change somewhere in one of the FF's Updates.

I didn't see anything with a quick search over at BuggyZilla:

https://bugzilla.mozilla.org/


~Pj

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Is Firefox already started when you turn on the LCD screen?

Firefox normally reads the window settings from xulstore.json. This file would store the last used screen dimensions and position.

Try to rename/remove xulstore.json and if present delete localstore.rdf in the Firefox profile folder with Firefox closed.

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:preferences page.

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I have firefox on the startup folder, so it automatically starts after I turn on the PC, and after win 7 boot up

the boot up firefox is bigger than my max. screen size of 3840x2160, so even if it stores my last used dimensions, it shouldn't be at a resolution bigger than 3840x2160

however, I have 2 screen on my PC. This 40" UHD and a 60" 1920x1080 TV as a 2nd screen. it's Separate. it is Never setup as 1 big screen. So unless firefox somehow merge the 2 screens

Further, this problem occurs in the past 2 mth. or so, when I take those update, meaning a slightly older ver. firefox doesn't have this problem

Are you thinking xulstore.json is corrupted?