When trying to close the window, the window glass will drop a few inches after reaching the closed position.This can happen on any window that has the automatic closing feature.
The system that prevents you from being injured by the automatically closing windows is called the "pinch protection system" and this system needs to be reset, reprogrammed or is defective.
In your owners manual you will find instructions on how to reset this feature. If that doesn't work, you'll need a Saab repair shop or Dealership to check for a software update for the pinch protection system, or see if there is a defective part. Have the shop reference the Saab Technical Service Bulletin (TSB #831-2639)to help address this issue.