title: Libqt 5 based applications have big icons and fonts and scaling issues
body: <p>Since I updated to QT 5 (Ubuntu 16.04), all applications (VLC, TexStudio, Texmaker ...) that use QT 5 have problems scaling, and every time I disconnect my laptop from the external screen , the incons and fonts are big and pixalated.</p>
  
  <p>If any one had the same issue or is familiar with the problem, I would appreciate the help. </p>