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Now that Visual Studio 2012 has a somewhat usable dark theme, I'm starting to actually reduce a bit of strain on my eyes at work.

The problem now is that I have two monitors, generally with a maximized visual studio on the left and a maximized Firefox on the right. All that darkness I'm getting from Visual Studio now is being overshadowed (pun intended) by the brightness of the Firefox window next to it.

Installing a dark theme for Firefox would help a little, but it's mostly the content of web pages that's the problem, not the chrome around them. So I had a thought that it would be useful if Firefox could just go dark when I focus on another window (i.e. turn down the brightness on the content pane so white backgrounds become gray, etc). Does anybody know of an add on that will accomplish something like that?

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up vote 6 down vote accepted

If you have a dark wallpaper and there are no windows behind the Firefox window, you can use AutoHotkey to make the window transparent when it loses focus, and opaque when it gains focus. I've come up with a simple script that should also be light on resources:

SetTitleMatchMode, RegEx

Firefox := "- Mozilla Firefox$"

while (true)
    IfWinActive, % Firefox
        WinSet, Trans, 255

        WinWaitNotActive, % Firefox
            WinSet, Trans, 127
        WinWaitActive, % Firefox
            WinSet, Trans, 255

Video Demonstration:

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I've experienced with AutoIT, some CPU's have problems dealing with the while (true). You might want to add a little sleep (like sleep (50)). You won't notice the 50 ms "lag" caused, and the CPU is happier with this. But +1 for the effort. – Devator Jun 21 '12 at 7:24
@Devator I don't know if that applies here. The WinWait commands make it so the script can sit idly by for an arbitrary length of time. – iglvzx Jun 21 '12 at 7:25
Ah, sorry. You are right. Need some more coffee. – Devator Jun 21 '12 at 7:26
@Devator Don't sweat it. Originally, before posting here, I had the script call itself at the end, creating a new process each time. Haha. That's when I realized I needed a lighter approach. :) – iglvzx Jun 21 '12 at 7:28

It might be worth giving JediConcentrate a look, whilst it isn't a plugin specifically for Firefox, it will probably acheive the effect you're looking for.

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After looking it up, JediConcentrate seems the best idea. Another program doing the same thing that I found is Ghoster : didn't want to steal @arpz's thunder, so added this in comment. – lornix Jun 20 '12 at 16:28
Too kind sir :) – arpz Jun 20 '12 at 18:46
Hmm, JediConcentrate doesn't seem to be working at all. I'm assuming that's due to the fact that it was written in 2006 and is therefore probably not compatible with windows 7 64 bit. ghoster only seems to work on one monitor. – Mike Ruhlin Jun 20 '12 at 20:19
(despite a "multimon" pref in the ghoster.ini file) – Mike Ruhlin Jun 20 '12 at 20:20

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