I'm testing our 3D viewers with the new release version 2.4.0 on Windows 10 with OpenJDK 11 and I have an issue with the com.jogamp.opengl.awt.GLCanvas.
The canvas now flickers when resized and sometimes nothing is displayed. This issue is related to the background erase which doesn't seem to be properly disabled now.
It can be easily reproduced with the JOGLQuad example (https://jogamp.org/wiki/index.php/Rudimentary_standalone_example_using_the_fixed_pipeline_by_Julien_Gouesse
) by removing the line "frame.setResizable(false);" and resizing the canvas.
If you remove the animator startup, you will see that sometimes nothing is displayed.
No issue with the com.jogamp.newt.awt.NewtCanvasAWT. I have not tested on Linux platforms yet.
Before filing a bug report, I wanted to know if the use of the property "sun.awt.noerasebackground" is now recommended.
For your information, you can see below the difference in calling the "disableBackgroundErase" method between 2.3.2 and 2.4.0