Pause script execution on exceptions

You can configure Web Inspector to pause the execution of scripts whenever exceptions are thrown. A tri-state toggle allows you to specify whether to pause for all exceptions, for only uncaught exceptions, or for no exceptions.
  1. Click the Sources icon on the toolbar to display the Sources panel.
  2. Use the Exceptions button in the status bar at the bottom to choose one of the following behaviors:
    • To pause on all exceptions, click the Exceptions button until the icon turns blue.
    • To pause only on uncaught exceptions, click the Exceptions button until the icon turns red.
    • To not pause on any exceptions, click the Exceptions button until the icon turns gray.