Sometimes Forte for Java crashes unexpectedly with messages like these:

      X Error of failed request: BadWindow (invalid Window parameter)
        Major opcode of failed request: 38 (X_QueryPointer)
        Resource id in failed request: 0x0
        Serial number of failed request: 42223
        Current serial number in output stream: 42223
        

      X Error of failed request: BadWindow (invalid Window parameter)
        Major opcode of failed request: 38 (X_QueryPointer)
        Resource id in failed request: 0x0
        Serial number of failed request: 22534
        Current serial number in output stream: 22534

Steps to reproduce:
1. run F4J on JDK 1.3
2. Open example MemoryView
3. In Form editor copy the JTextField1, paste it somewhere and delete it (repeat several times)
4. Then move (several times) with ScrollBar in the Editor window
5. The ide crashes with the text mentioned above

It happens only if we run two instances of Forte at once.