Safari screen glitch/flicker during full screen video

Discussion in 'macOS Mojave (10.14)' started by spikie, Feb 7, 2019.

  1. spikie, Feb 7, 2019
    Last edited: Feb 7, 2019

    spikie macrumors member

    Oct 24, 2013

    Video here:

    I have this problem where whenever I am watching something in Safari in full screen, randomly a frame from an old video (watched several hours before) would start flickering every time I move the mouse. As you can see in the video, there is a random bright frame that flashes up every single time I move the cursor. Except that the frame is not really random, and I recognise it from a video that I watched earlier this morning. The frame will stop flashing if I don't move the mouse. However, if I have subtitles turned on, the frame will keep flashing as soon as one line of the subtitle disappears, and it will keep flashing indefinitely.

    This has been happening for years, through several macOS versions.

    I am using a mid-2012 cMPB 13", running on 10.14.2 Mojave. While the laptop is old, it is running the latest version of macOS, and the fact is that I have had this problem in every version of macOS that ever ran on this.

    It is a strange issue, and the only solution I found is to restart the mac, but the problem keeps coming back, it happens every day. I have not managed to find a similar issue by anyone, where one frame from a previously watched video is retained and keeps flashing up for hours.

    Any advice on how I could go about troubleshooting this?
  2. spikie thread starter macrumors member

    Oct 24, 2013
    bump, anyone? Or can anyone find a similar issue raised by anyone before?
  3. NielsO macrumors newbie


    Jul 28, 2017
    I have head similar issues. But after updating and using newer versions of MacOS the problems were gone.
    Maybe updating to 10.14.3 will solve your problems. Return to this topic when it won't.
  4. lillefot macrumors newbie


    Nov 1, 2014
    Oslo, Norway
    Try unchecking "Automatic Graphics Switching" under "Energy saving". That helped for me, found it after some googling. I'm not sure what the effects are of unchecking it (apart from the flickering stopped on my Mac) though.
  5. spikie thread starter macrumors member

    Oct 24, 2013
    Thanks for the suggestion, but it is a 13" MacBook Pro, it doesn't have a dGPU, so unfortunately I don't have that option in the Energy Saver settings.

    I have updated to 10.14.3, I will come back here once the problem returns, but as I mentioned I had this problem for years all through every iteration of macOS.
  6. givemeanapple macrumors Demi-God


    Oct 2, 2016
    This is an issue with the Integrated graphics and Apple's Software. Using the dGPU solves the issue, if your MB doesn't have a dGPU then theres nothing you can do to fix it unless waiting for Apple to pretend they care and fix the issue that's been reported for years. You can also switch to Chrome, it's a win win.
  7. kakinc, Feb 10, 2019
    Last edited: Feb 10, 2019

    kakinc macrumors member

    Jun 16, 2018
    Watch it using Chrome browser.
    Thats the only solution I found working.

    *Sometime you may see snapshot of video you previously played showing up (flashes) while playing another video. (Safari)
    Only solution I find for this is to restart the machine.

    *Consider yourself lucky, this used to happen to youtube too...
    But I think youtube changed the way they handle fullscreen, now you can scroll down in fullscreen on youtube.
  8. NielsO macrumors newbie


    Jul 28, 2017
    I have a dGPU but if I turn the automatic graphic switching, it will also use the dGPU when I use my macbook on it's battery. This will result in a faster draining of the battery.
    But it seems to overcome the issue.
  9. spikie, Feb 11, 2019
    Last edited: Feb 11, 2019

    spikie thread starter macrumors member

    Oct 24, 2013
    Yes, you are absolutely right, Chrome browser does not suffer from this issue, and as you mentioned, restarting the machine solves the issue. It is just such a pain because I find Safari a lot more enjoyable to use. I can confirm that the issue is still present as of the current macOS 10.14.3, as expected.

    I just seriously cannot believe that an issue like this is still present after several years of updates. Some more general observations, maybe it gives someone an idea to pinpoint the cause:
    • Only affects Safari, other browsers work fine
    • Does not go away by simply restarting Safari, need to restart entire machine
    • The cursor arrow gets hidden automatically (normal behaviour) when watching full screen video, but the glitch happens right when the cursor gets hidden
    • If subtitles are enabled, glitch keeps happening indefinitely, every time a single line of subtitle disappears
    • Glitch does not happen if the tray, menubar or the video control bar is visible, I assume because in all of these scenarios the mouse cursor does not get hidden (as it is pointing at something)
    Therefore, given the above, I strongly believe it has something to do with the fact that cursor gets automatically hidden when watching full screen video. I do not understand why it happens more often as subtitles appear and disappear though.
    I have no idea what to change, if anyone has any clue, all suggestions are welcome.

    Yeah, you are probably correct with that conclusion. It's doubtful that this will ever get solved, I am just hoping that it does not show up on my next Mac.
    As you said, it's probably an issue with the Integrated Graphics and Safari, but then there has to be something that can be deleted/modified in the Safari folder that will stop this behaviour. I mean the image that flashes up must be stored somewhere, a location that gets erased when restarting the machine, but not when simply closing Safari.

Share This Page