title: qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found."
body: <p>I have installed <a href="https://berkeleyautomation.github.io/gqcnn/install/install.html#run-pip-installation" rel="noreferrer">gqcnn</a>, <a href="https://github.com/stepjam/PyRep" rel="noreferrer">Pyrep</a> and <a href="https://berkeleyautomation.github.io/autolab_core/install/install.html#option-1-pip" rel="noreferrer">autolab_core</a>. After that, I executed the code that my coworker wrote and, it ran fine on his computer.</p>
  <p>However, I cannot run the code. The occurred error was</p>
  <pre><code>python3.7/site-packages/cv2/qt/plugins/platforms&quot; ...
  QFactoryLoader::QFactoryLoader() looking at &quot;/home/bak/anaconda3/envs/pyrep/lib/python3.7/site-packages/cv2/qt/plugins/platforms/libqxcb.so&quot;
  Found metadata in lib /home/bak/anaconda3/envs/pyrep/lib/python3.7/site-packages/cv2/qt/plugins/platforms/libqxcb.so, metadata=
  {
      &quot;IID&quot;: &quot;org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3&quot;,
      &quot;MetaData&quot;: {
          &quot;Keys&quot;: [
              &quot;xcb&quot;
          ]
      },
      &quot;archreq&quot;: 0,
      &quot;className&quot;: &quot;QXcbIntegrationPlugin&quot;,
      &quot;debug&quot;: false,
      &quot;version&quot;: 331520
  }
  
  
  In /home/bak/anaconda3/envs/pyrep/lib/python3.7/site-packages/cv2/qt/plugins/platforms/libqxcb.so:
    Plugin uses incompatible Qt library (5.15.0) [release]
  &quot;The plugin '/home/bak/anaconda3/envs/pyrep/lib/python3.7/site-packages/cv2/qt/plugins/platforms/libqxcb.so' uses incompatible Qt library. (5.15.0) [release]&quot; 
           not a plugin
  QFactoryLoader::QFactoryLoader() checking directory path &quot;/home/bak/anaconda3/envs/pyrep/plugins/platforms&quot; ...
  QFactoryLoader::QFactoryLoader() looking at &quot;/home/bak/anaconda3/envs/pyrep/plugins/platforms/libqeglfs.so&quot;
  Found metadata in lib /home/bak/anaconda3/envs/pyrep/plugins/platforms/libqeglfs.so, metadata=
  {
      &quot;IID&quot;: &quot;org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3&quot;,
      &quot;MetaData&quot;: {
          &quot;Keys&quot;: [
              &quot;eglfs&quot;
          ]
      },
      &quot;className&quot;: &quot;QEglFSIntegrationPlugin&quot;,
      &quot;debug&quot;: false,
      &quot;version&quot;: 329991
  }
  
  
  Got keys from plugin meta data (&quot;eglfs&quot;)
  QFactoryLoader::QFactoryLoader() looking at &quot;/home/bak/anaconda3/envs/pyrep/plugins/platforms/libqminimal.so&quot;
  Found metadata in lib /home/bak/anaconda3/envs/pyrep/plugins/platforms/libqminimal.so, metadata=
  {
      &quot;IID&quot;: &quot;org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3&quot;,
      &quot;MetaData&quot;: {
          &quot;Keys&quot;: [
              &quot;minimal&quot;
          ]
      },
      &quot;className&quot;: &quot;QMinimalIntegrationPlugin&quot;,
      &quot;debug&quot;: false,
      &quot;version&quot;: 329991
  }
  
  
  Got keys from plugin meta data (&quot;minimal&quot;)
  QFactoryLoader::QFactoryLoader() looking at &quot;/home/bak/anaconda3/envs/pyrep/plugins/platforms/libqminimalegl.so&quot;
  Found metadata in lib /home/bak/anaconda3/envs/pyrep/plugins/platforms/libqminimalegl.so, metadata=
  {
      &quot;IID&quot;: &quot;org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3&quot;,
      &quot;MetaData&quot;: {
          &quot;Keys&quot;: [
              &quot;minimalegl&quot;
          ]
      },
      &quot;className&quot;: &quot;QMinimalEglIntegrationPlugin&quot;,
      &quot;debug&quot;: false,
      &quot;version&quot;: 329991
  }
  
  
  Got keys from plugin meta data (&quot;minimalegl&quot;)
  QFactoryLoader::QFactoryLoader() looking at &quot;/home/bak/anaconda3/envs/pyrep/plugins/platforms/libqoffscreen.so&quot;
  Found metadata in lib /home/bak/anaconda3/envs/pyrep/plugins/platforms/libqoffscreen.so, metadata=
  {
      &quot;IID&quot;: &quot;org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3&quot;,
      &quot;MetaData&quot;: {
          &quot;Keys&quot;: [
              &quot;offscreen&quot;
          ]
      },
      &quot;className&quot;: &quot;QOffscreenIntegrationPlugin&quot;,
      &quot;debug&quot;: false,
      &quot;version&quot;: 329991
  }
  
  
  Got keys from plugin meta data (&quot;offscreen&quot;)
  QFactoryLoader::QFactoryLoader() looking at &quot;/home/bak/anaconda3/envs/pyrep/plugins/platforms/libqvnc.so&quot;
  Found metadata in lib /home/bak/anaconda3/envs/pyrep/plugins/platforms/libqvnc.so, metadata=
  {
      &quot;IID&quot;: &quot;org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3&quot;,
      &quot;MetaData&quot;: {
          &quot;Keys&quot;: [
              &quot;vnc&quot;
          ]
      },
      &quot;className&quot;: &quot;QVncIntegrationPlugin&quot;,
      &quot;debug&quot;: false,
      &quot;version&quot;: 329991
  }
  
  
  Got keys from plugin meta data (&quot;vnc&quot;)
  QFactoryLoader::QFactoryLoader() looking at &quot;/home/bak/anaconda3/envs/pyrep/plugins/platforms/libqxcb.so&quot;
  Found metadata in lib /home/bak/anaconda3/envs/pyrep/plugins/platforms/libqxcb.so, metadata=
  {
      &quot;IID&quot;: &quot;org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3&quot;,
      &quot;MetaData&quot;: {
          &quot;Keys&quot;: [
              &quot;xcb&quot;
          ]
      },
      &quot;className&quot;: &quot;QXcbIntegrationPlugin&quot;,
      &quot;debug&quot;: false,
      &quot;version&quot;: 329991
  }
  
  
  Got keys from plugin meta data (&quot;xcb&quot;)
  QFactoryLoader::QFactoryLoader() checking directory path &quot;/home/bak/anaconda3/envs/pyrep/bin/platforms&quot; ...
  Cannot load library /home/bak/anaconda3/envs/pyrep/plugins/platforms/libqxcb.so: (/home/bak/anaconda3/envs/pyrep/plugins/platforms/../../lib/libQt5XcbQpa.so.5: symbol _ZN11QFontEngine14bitmapForGlyphEj6QFixedRK10QTransform version Qt_5_PRIVATE_API not defined in file libQt5Gui.so.5 with link time reference)
  QLibraryPrivate::loadPlugin failed on &quot;/home/bak/anaconda3/envs/pyrep/plugins/platforms/libqxcb.so&quot; : &quot;Cannot load library /home/bak/anaconda3/envs/pyrep/plugins/platforms/libqxcb.so: (/home/bak/anaconda3/envs/pyrep/plugins/platforms/../../lib/libQt5XcbQpa.so.5: symbol _ZN11QFontEngine14bitmapForGlyphEj6QFixedRK10QTransform version Qt_5_PRIVATE_API not defined in file libQt5Gui.so.5 with link time reference)&quot;
  qt.qpa.plugin: Could not load the Qt platform plugin &quot;xcb&quot; in &quot;/home/bak/anaconda3/envs/pyrep/lib/python3.7/site-packages/cv2/qt/plugins&quot; even though it was found.
  This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
  
  Available platform plugins are: eglfs, minimal, minimalegl, offscreen, vnc, xcb.
  </code></pre>
  <p>If you want to see the full error in detail, please see <a href="https://docs.google.com/document/d/1ATmeucjVbamlPL1rYoi7ZLm84inzPTNhJM1ygawO-H0/edit?usp=sharing" rel="noreferrer">here</a>.
  '/pyrep/' in above is my anaconda environment name.</p>
  <p>It seems to be caused by qt. But I cannot fix this problem.</p>
  <p>What should I do to solve this problem?</p>