internal/uidriver/glfw: Bug fix: FramebufferSize callback was not called when the window size was not changed

Closes #1580

internal/uidriver/glfw/ui.go

@@ -1177,21 +1177,24 @@ func (u *UserInterface) setWindowSize(width, height int, fullscreen bool) {
 		newW := width
 		newH := height
 		if oldW != newW || oldH != newH {
-			ch := make(chan struct{})
+			ch := make(chan struct{}, 1)
 			u.window.SetFramebufferSizeCallback(func(_ *glfw.Window, _, _ int) {
-				u.window.SetFramebufferSizeCallback(nil)
-				close(ch)
+				ch <- struct{}{}
 			})
 			u.window.SetSize(newW, newH)
-		event:
-			for {
-				glfw.PollEvents()
-				select {
-				case <-ch:
-					break event
-				default:
+			if w, h := u.window.GetSize(); w != oldW || h != oldH {
+			event:
+				for {
+					glfw.PollEvents()
+					select {
+					case <-ch:
+						break event
+					default:
+					}
 				}
 			}
+			u.window.SetFramebufferSizeCallback(nil)
+			close(ch)
 		}
 
 		// Window title might be lost on macOS after coming back from fullscreen.