Further info, it may be that QtC spawns several processes, which create a surface each:
ps ax | grep qtcrea 16716 pts/10 SNl 0:02 qtcreator 16737 pts/10 ZN 0:00 [qtcreator] <defunct> 16738 pts/10 ZN 0:00 [qtcreator] <defunct>
While the child surfaces die, QtC itself hasn't.
Further info, it may be that QtC spawns several processes, which create a surface each:
ps ax | grep qtcrea
16716 pts/10 SNl 0:02 qtcreator
16737 pts/10 ZN 0:00 [qtcreator] <defunct>
16738 pts/10 ZN 0:00 [qtcreator] <defunct>
While the child surfaces die, QtC itself hasn't.