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  1. Qt
  2. QTBUG-74492

QWebEngineView: A blinking white dot displays on dark website



    • Type: Bug
    • Status: Closed
    • Priority: P2: Important
    • Resolution: Done
    • Affects Version/s: 5.12.0, 5.12.2
    • Fix Version/s: 5.12.5, 5.13.1, 5.14.0 Alpha
    • Component/s: GUI: OpenGL
    • Labels:
    • Environment:
    • Platform/s:
    • Commits:
      cc873ec23a98ac32d10ac5fa569792fde2f6b2c8 (qt/qtbase/5.12)


      Simplified bug report

      A blinking white dot appears on the window / widget when using OpenGL on Windows.

      According to a few people it can be reproduced with multiple examples:

      1. "Qt Quick Controls - Gallery" example: qt_source/qtquickcontrols2/examples/quickcontrols2/gallery/gallery.pro
      2. https://bugreports.qt.io/secure/attachment/84270/84270_mcve_74492.cpp
      3. import QtQuick 2.12
        import QtQuick.Window 2.12
        Window {    
          visible: true    
          width: 640    
          height: 480    
          color: 'black'   
          TextEdit {        
            anchors.centerIn: parent        
            width: 200        
            height: 20        
            text: 'Sample text'        
            color: 'red'    

      Platform is Windows, details environment info is in Environment field.

      Original bug report below

      Note that this is independent of WebEngine and also happens with a variety of other Qt modules that use OpenGL (in contrast to OpenGL ES or software rendering).

      For example open https://www.speedtest.net/fr for example you will see a blinking  white dot at the middle of the webview parasiting the display

      This blinking dot shows up in many other website when the background is dark. 

      The blinking dot shows up also on some youtube video.

      Again you can see the blinking dot on the error when you open any metacafe video, (metacafe doesn't work with webengine it's another bug, but the intersting thing here is the white dot) 

      Reportedly introduced by "Fix automatic showing/hiding of the Windows 10 on-screen keyboard" 3d867b8 https://codereview.qt-project.org/c/qt/qtbase/+/232927


        1. 2019-05-28_13-20-00.gif
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          BPL BPL
        2. 2019-05-28_13-20-55.gif
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        3. 2019-05-28_14-53-22.gif
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        4. bpl_system_information.txt
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        5. evil_dot_1.png
          49 kB
          Jakub Narolewski
        6. evil_dot_2.png
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          Jakub Narolewski
        7. evil_dot_3.png
          137 kB
          Jakub Narolewski
        8. evil_dot_4.png
          31 kB
          Jakub Narolewski
        9. image-2019-03-16-20-34-45-254.png
          234 kB
          Dragoon Gryffoon
        10. image-2019-03-16-20-35-58-680.png
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          Dragoon Gryffoon
        11. image-2019-03-16-20-47-10-288.png
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          Dragoon Gryffoon
        12. mcve_74492.cpp
          0.7 kB
          BPL BPL
        13. mcve_74492.py
          1 kB
          BPL BPL
        14. mcve_andre_74492.7z
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        15. qtbug74492.qml
          0.3 kB
          Friedemann Kleint
        16. qtdiag.txt
          8 kB
          Jakub Narolewski
        17. Screen Recording 2019-05-28 at 15.45.16.mov
          4.48 MB
          Igor Bugaev
        18. Screenshot 2019-07-02 at 18.35.00.png
          1.27 MB
          Igor Bugaev

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              • Assignee:
                anrocha André De La Rocha
                navis-raven Dragoon Gryffoon
              • Votes:
                4 Vote for this issue
                12 Start watching this issue


                • Created:

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