Spy-js Tool Window
The tool window is available only when the Spy-js plugin is enabled. The plugin is not bundled with PhpStorm, but it can be installed from the JetBrains plugin repository as described in Installing, Updating and Uninstalling Repository Plugins and Enabling and Disabling Plugins.
The tool window opens when you launch a run configuration of the type Spy-js or Spy-js for NodeJS. As soon as the Spy-js tool captures an event, it shows the event itself, its details, and stack-traces. By clicking an event, you can open the trace file, which is a prettified source file with the script that the event launched.
The tool window consists of a common toolbar and two tabs with panes: