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I messed up about:config

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I got into about:config trying to change font size and have it all messed up now. Everything is about the size of my thumb and I can't get back into about:config in order to make the font big enough to see. Any suggestions? I am using a Mac book pro. Thanks

I got into about:config trying to change font size and have it all messed up now. Everything is about the size of my thumb and I can't get back into about:config in order to make the font big enough to see. Any suggestions? I am using a Mac book pro. Thanks

Chosen solution

Hi air2water,

Don't you just hate it when that happens .....

I'm a 'Windows person', I hope this will work on Mac as well :

Let's try this :

Open Firefox and press Ctrl +L (whichwill put the focus into the location bar)

Type about:config

Press Enter twice

Type devpix

Press the Tab key

Press Enter

Type 1.0

Press Enter again, and with a bit of luck you should be able to see what you're doing again (fingers crossed) .......

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All Replies (7)

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Chosen Solution

Hi air2water,

Don't you just hate it when that happens .....

I'm a 'Windows person', I hope this will work on Mac as well :

Let's try this :

Open Firefox and press Ctrl +L (whichwill put the focus into the location bar)

Type about:config

Press Enter twice

Type devpix

Press the Tab key

Press Enter

Type 1.0

Press Enter again, and with a bit of luck you should be able to see what you're doing again (fingers crossed) .......

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I tried that 20 times because I saw another post. On a Mac you need to hit command+L to put focus into location bar. Got so frustrated I deleted Firefox and am using Safari right now. I really liked Firefox, if I could only figure a way to see it. I am not even sure what shows up when I open Firefox because it is so tiny.

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air2water said

I tried that 20 times because I saw another post. On a Mac you need to hit command+L to put focus into location bar. Got so frustrated I deleted Firefox and am using Safari right now. I really liked Firefox, if I could only figure a way to see it. I am not even sure what shows up when I open Firefox because it is so tiny.

Ahhh, of course : on Mac it's not 'Ctrl', but 'Cmnd' (sorry  !)

So, you had tried that already and it didn't work - well, again : my bad, cause when you said that everything was as big as your thumb, I was thinking : huge .....

Probably a rhetorical (and maybe even dumb) question : but have you tried to use the keys on your keyboard to zoom in  ?

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'Found this :

https://alvinalexander.com/blog/post/mac-os-x/how-zoom-in-zoom-out-mac-osx-screen

If that doesn't at least get you back to being able to resetting the prefs on the 'about:config' page, then I can only hope that somebody else will be able to come up with the perfect solution for you .....

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I got a magnifying glass and was able to barely see about:config. I reset the line ( layout.css.devPixelsPerPx) I am now back in business. Thanks so much for the help. Firefox--here we come.

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that you can also edit the prefs.js file in the profile folder and edit/remove the offending line if this happens again.

The Firefox profile folder is in a hidden location in the home directory.

  • ~/Library/Application Support/Firefox/Profiles/<profile>/

In Mac OS X v10.7 and later, the ~/Library folder in the Home directory is a hidden folder.

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Murphy said

... have you tried to use the keys on your keyboard to zoom in  ?

I like Murphy's suggestion:

While you're on the about:config page, hold down Command and tap the + key repeatedly to enlarge it as much as Firefox can enlarge (300%, I think). Hopefully then it will be readable and you can reset the problem setting. Then press Command+0 to restore normal zoom on the page.

But anyway, the magnifying glass works, too.