Strange bug

Hi!

Today, I was downloading some stuff, like any other day and I noticed the progress window wasn't looking right (it was almost empty), So I opened the main window and it looked like the attached screenshot. Tried to close from the tray icon,but a dialog saying "a required resource was not found" appeared. I had to kill the process from the task manager. Re-opened Ant and it looked right again

see here: https://i.servimg.com/u/f28/20/10/75/21/ant12.png

There was an accident of the object of display of the graphic context.
Difficult to diagnose the cause without a confident reproduction of such an bug.

Nothing to do , I guess. it has worked fine ever since. only that isolated incident