With the current implementation of gray box painting in Java Plug-in 1.4, a processing thread and a timer thread is used for forcing repaint in gray box every second. The problem is that it takes up too much resources for small applets because two additional threads are created. Also, because timer is used, any applet using timer for rendering itself may run into problem because of stealing CPU cycles from the graybox timer. This slowup the startup time for most applets. This is a performance bug.