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FF 61 Ubuntu 18.04 watching stream line video dim light problem

  • 4 replies
  • 1 has this problem
  • 22 views
  • Last reply by michaelbr

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I have a new installation of Ubuntu 18.04 and installed FF 61, when I watch an online video, after a while (around 5 min), the light start to dim out, then the screen will lock up, I read on the web that Caffeine addon could solve this problem, installed, but can't see the coffee cup on FF, then I found later that Caffeine is no longer supported, but there is another addon Keep Awake doing similar thing, installed and seems to work, few days later, when I opened FF again to watch online movie, Keep Awake does not work any longer, I can turn it on/off, still FF will dim the light after a while, so I went to Settings > Power > and turned off the Dim screen when inactive, but still FF keeps dimming the light after a while. Where's the setting to turn off the dim light in FF? TIA

I have a new installation of Ubuntu 18.04 and installed FF 61, when I watch an online video, after a while (around 5 min), the light start to dim out, then the screen will lock up, I read on the web that Caffeine addon could solve this problem, installed, but can't see the coffee cup on FF, then I found later that Caffeine is no longer supported, but there is another addon Keep Awake doing similar thing, installed and seems to work, few days later, when I opened FF again to watch online movie, Keep Awake does not work any longer, I can turn it on/off, still FF will dim the light after a while, so I went to Settings > Power > and turned off the Dim screen when inactive, but still FF keeps dimming the light after a while. Where's the setting to turn off the dim light in FF? TIA

All Replies (4)

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Hi

This does not sound like an issue with Firefox, but could be Ubuntu dimming the display.

I recomend that you have a look at the power and/or display settings to set timing for this and to turn it off (if required).

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Hi Seburo, thanks for your reply. I don't think it's OS problem for 2 reasons: 1) Dim light is already disabled as I mentioned in my post and watching video on FF still dims out the light. 2) watching video on the same site using Opera worked just fine, without disabling the Power setting. I'm not that knowledgeable about FF or Linux, I might be wrong.

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with firefox launched, type in the url bar: `about:config` and look for for `device.sensors.ambientLight.enabled` and set it to false and see if the issue persists.

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Corey 'linuxmodder' Sheldon said

with firefox launched, type in the url bar: `about:config` and look for for `device.sensors.ambientLight.enabled` and set it to false and see if the issue persists.

Hi Corey, actually my post is misleading, it's not a problem of dim light, I think what happens is FF senses there's no activity and lock the screen, so it dims the light then lock the screen. To answer you question, the device.sensors.ambientLight.enabled is already set to false.