How to get rid of title bar in KDE to maximize screen real estate?

  1. Use you favorite text editor to edit the file


    In some distributions the .kde4 directory is called .kde (or something else like .kdemod4)

  2. Add the line


    under the section [Windows]
    It should look something like this:


  3. Launch KRunner (Alt+F2) and run the command

    kwin --replace

    to restart KWin

  4. Go crazy and maximize every window in sight! Remember that you can unmaximize them from the window menu (Alt+F3) or from the task manager in your panel. If quick tiling is enabled (System Settings → Desktop → Screen Edges → Window Management), you can also use Alt+Left mouse button to unmaximize windows by dragging them

This is a suggestion copied from here.