[Pharo-project] System Window and OB model

Quitting a system/hierarchy browser opened with the ToolSet, fails to inform the close to the model OB browser . For example in the following code 1 doesnt get explored | window | window := ToolSet browse: Set selector: anyOne. window model announcer observe: OBCloseRequest do:[:ann| 1 explore ]. Did anybody had this problem before? Or solved it already? Fernando