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Only in Firefox, my entire screen dims occasionally. How do I disable this?

  • 4 replies
  • 18 have this problem
  • 4 views
  • Last reply by cor-el

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Only in Firefox, my entire screen dims. Sometimes it's when I scroll down a page, sometimes for no apparent reason. I haven't figured out the pattern yet. There are no error messages or dialog boxes. While on this page, it hasn't happened. but when I open a new tab, the screen instantly dims until the new page finishes loading. It seems it happens when Firefox is waiting for me to do something. Just now when I clicked on the area below where Firefox guessed at my plugins, my screen immediately dimmed. Five time since I started typing these last 2 sentences it has dimmed, and it's still dim now. It seems to brighten up when I move my mouse sometimes. It rarely brightens up when I start typing. The problem is that after the screen dims it's hard to see where/what I'm supposed to type/do on the screen.

Only in Firefox, my entire screen dims. Sometimes it's when I scroll down a page, sometimes for no apparent reason. I haven't figured out the pattern yet. There are no error messages or dialog boxes. While on this page, it hasn't happened. but when I open a new tab, the screen instantly dims until the new page finishes loading. It seems it happens when Firefox is waiting for me to do something. Just now when I clicked on the area below where Firefox guessed at my plugins, my screen immediately dimmed. Five time since I started typing these last 2 sentences it has dimmed, and it's still dim now. It seems to brighten up when I move my mouse sometimes. It rarely brightens up when I start typing. The problem is that after the screen dims it's hard to see where/what I'm supposed to type/do on the screen.

All Replies (4)

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If you can record a video of this with camstudio then I'd say it's likely software related. If the video shows no dimming at all, it's gotta be your hardware.

I'd try a different monitor tbh. If firefox has dimming settings that's news to me.

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camstudio did NOT show a dimming. Interesting that it happens only in Firefox.

Thanks for your response!! Any other ideas?

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You could try updating all of your add-ons first, and restarting firefox, but I'd try a different monitor first. No clue why only firefox would dim though...

There's an experimental add-on called black out that dims firefox but it doesn't look like you're running it.

If you want to cover all of your bases, open the device manager - and have windows check for display driver updates by right clicking it. Could be some strange driver bug.

You could also check your power settings, and tell Windows not to dim the screen - although what you're describing doesn't sound like Windows dimming the screen.

Modified by SeeD419

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If windows dims the screen then that usually indicates that the program isn't responding.

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).