base on software helix codec, continously to playback more files, switch from full screen mode to window mode, easy to lost video

After you manage to get into the state where video is not visible but audio is still playing, can you toggle back and forth from full screen to windowed mode and cause the video to be visible again?

This will effect the priority of the bug.

if I deal with all the drawingarea's Xevent inside helix engine, may fix this bug. but moblin-media will lose these events (for example: button press to do full-screen or un-fullscreen).
in theory, even I connect all drawingarea's Xevent to helix engine by event_filter, if I return GDK_FILTER_CONTINUE, moblin-media could also receive these event. but the fact is: moblin-media can't receiver these Xevent.
enum GdkFilterReturn
typedef enum {
  GDK_FILTER_CONTINUE, /* Event not handled, continue processesing */
  GDK_FILTER_TRANSLATE, /* Translated event stored */
  GDK_FILTER_REMOVE /* Terminate processing, removing event */
} GdkFilterReturn;
              If we return GDK_FILTER_CONTINUE, the X event should also come to other registered callback functions.
And it works well in sole application of gtk_test. (one is for event_filter, another is for g_signal_connect, both will be invoked).
But for two applications(moblin-media and dbus-server) share the event, if we return GDK_FILTER_CONTINUE in dbus-server; moblin-media will not receive the message.

I have connect "Expose" event of drawingarea to helix engine in current release, try to see any difference.
may try to connect all Xevent of drawingarea (except Mouse click event) to helix engine. however, hard to do that completely, for example "FocusIn" also depend on Mouse event.

Nominating for M11. We have several ideas in the works here, and will find a way to make this work