Merge branch 'fullscreens-added-removed' of https://github.com/x11clone/x11clone

diff --cc vncviewer/DesktopWindow.cxx
index 7936deb7fbc733ac577a1b1829780f6d70c9406f,f0aae11a024328727e8d3dfa469d46222e2bac62..ef023a5ba6f8ec43eb2aec03750eeb1f0e4ef504
--- 1/vncviewer/DesktopWindow.cxx
--- 2/vncviewer/DesktopWindow.cxx
+++ b/vncviewer/DesktopWindow.cxx
@@@ -832,14 -690,30 +849,36 @@@ int DesktopWindow::fltkHandle(int event
  {
    int ret;
  
 +  // FLTK keeps spamming bogus FL_MOVE events if _any_ X event is
 +  // received with the mouse pointer outside our windows
 +  // https://github.com/fltk/fltk/issues/76
 +  if ((event == FL_MOVE) && (win == NULL))
 +    return 0;
 +
    ret = Fl::handle_(event, win);
  
+   switch (event) {
+   case FL_SCREEN_CONFIGURATION_CHANGED:
+     // Screens removed or added. Recreate fullscreen window if
+     // necessary. On Windows, adding a second screen only works
+     // reliable if we are using a timer. Otherwise, the window will
+     // not be resized to cover the new screen. A timer makes sense
+     // also on other systems, to make sure that whatever desktop
+     // environment has a chance to deal with things before we do.
+     // Please note that when using FullscreenSystemKeys on macOS, the
+     // display configuration cannot be changed: macOS will not detect
+     // added or removed screens and there will be no
+     // FL_SCREEN_CONFIGURATION_CHANGED event. This is by design:
+     // "When you capture a display, you have exclusive use of the
+     // display. Other applications and system services are not allowed
+     // to use the display or change its configuration. In addition,
+     // they are not notified of display changes"
+     if (staticSelf->fullscreen_active()) {
+       Fl::remove_timeout(reconfigureFullscreen, staticSelf);
+       Fl::add_timeout(0.5, reconfigureFullscreen, staticSelf);
+     }
+   }
+ 
    // This is hackish and the result of the dodgy focus handling in FLTK.
    // The basic problem is that FLTK's view of focus and the system's tend
    // to differ, and as a result we do not see all the FL_FOCUS events we

diff --cc vncviewer/DesktopWindow.h
Simple merge