The second window is fully transparent!

Hello,
when I create the second window(via my menu entry) I find that it is fully transparent but I want it to be of zero transparency as the first window is. I could not find the way to establish zero transparency for the second window. I hope it is possible. How?

Thank you in advance
Oleg

Be sure to do that on your second window :

glClearColor( 1.0f,1.0f,1.0f,1.0f);
glClear(GL_COLOR_BUFFER_BIT);

Thank you,
it’s helped.
Regards
Oleg