I'm replying to my own message to provide some solutions I found to the problems I reported. First, regarding inaccessible window header bar, one must use the

I'm replying to my own message to provide some solutions I found to the problems I reported. First, regarding inaccessible window header bar, one must use the alt-right click magic action to display the window manager menu and select the move window. This works wherever we click in the window. The other menu commands might also be useful. However, my opinion is that it is bad UX and inefficient. Second, regarding NoMachine, I tested Xubuntu which doesn't depend on 3D accelerator and with some trick it can be used as an ersatz of Ubuntu. For the trick that works see here: https://answers.launchpad.net/ubuntu/+question/157817 https://answers.launchpad.net/ubuntu/+question/157817 One widget is not working, but it is not critical.