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QXcbConnection couldnt connect to display

  • OK everyone, read my story.....
    Im employed as core developer of some VR app (I (=me)) am restricted as to revealing codinity
    We have HPE physical server and we host our dev-env

    Now, we also needed Cloud - the best is AWS EC2, so we picked one of their instances, made it Reserved (RI) for 1year, chosen Ubuntu, started and..... holy shit - blazing fast.........

    Bundled with Ubuntu, there was PhantomJS - no need to introduce I hope...... but ..... refusing to start. Typing phantomjs phantom/test.js was giving QXcbConnection: Could not connect to display PhantomJS has crashed. Please read the bug reporting guide at <> and file a bug report. Aborted (core dumped)

    What the FUCK ???? Brand new instance (=with NOTHING installed by user) and something not working? Did 2 things::

    • let AWS know they have broken package, and

    • uninstalled bundled version, replacing it with same version downloaded from

    But, as its always like this when Im doing things, thie above error is still visible where it was.


    I assume its obvious that server does not need proper display (like X, Wayland and alike). If not for anything, for security reasons. Having X's installed (and accessible) on server opens many possibilities for people with unclear intentions.

    So - whats this message means? Whats wrong?

  • Lifetime Qt Champion

    seems more of a phantomjs issue than Qt.

  • Wrong. Its neither PJS nor QT.

    Its related to Debain (see this)
    Anyway - thanks for help

  • Lifetime Qt Champion


    Ok thx for reporting back.
    happy holidays

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