OnWindowOpen
Triggers a script to run each time you open a window of a database file.
When the script runs
After a window is opened or after OnFirstWindowOpen (if it is selected in the Script Triggers tab) is activated.
Modes in which the trigger can be used
OnWindowOpen activates before FileMaker Pro enters a mode.
Result
None.
Originated in
FileMaker Pro 12.0
Notes
You can also trigger a script this way when you open a window for a hidden file previously opened via a script or relationship.
Related topics 
Setting up script triggers
Setting script triggers for layouts
Setting script triggers for objects