title: Re-create FBO (frame buffer object) each frame
body: <p>I would like to create FBO but that will be "shared" between all contexts.
  Because an FBO is container and can not be "shared", but only its buffers, I thought to do the follow:</p>
  
  <ol>
  <li><p>Create an object FBODescriptor that is a descriptor of the desired FBO, it also contains opengl buffers that are shared.</p></li>
  <li><p>At <em>each</em> frame, and in any context that is active, I create the FBO (so it is available for the current context), attach to it the buffers, and delete the FBO container after the rendering. </p></li>
  </ol>
  
  <p>In this way, I have a desired FBO that is available for any context. </p>
  
  <p>My assumption is that because the resources buffers are existing and no need to re-create them each frame but only the FBO container, it doesn't have a meaningful penalty. </p>
  
  <p>May it works?</p>