Remove window title bar, but save frame e.t.c

Is it possible to remove title bar (with title and control buttons like close e.t.c) on window, but save window frame and other effects?

Undecorated window has nothing, not only title bar.

I need something like that (on Windows), not just floating panel
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You could specify a window without a title (i.e. use “” as the window title in glfwCreateWindow) and set the GLFW_RESIZABLE hint to false to remove resize buttons however the close button will still remain.

For more control, GLFW has native access functionality which you could use to get the hwnd and then alter the style using SetWindowLong().

Alternatively you could draw your own upper border with an undecorated window.