IntelliJ IDEA 2021.2 Help

Configuring JavaScript debugger

Debugging JavaScript in IntelliJ IDEA is supported through the JavaScript Debugger plugin. The JavaScript Debugger plugin is bundled with IntelliJ IDEA and activated by default. If the plugin is disabled, enable it on the Installed tab of the Settings/Preferences | Plugins page, as described in Managing plugins.

To ensure successful debugging, it is enough to specify the built-in web server port and accept the default settings that IntelliJ IDEA suggests for other debugger options.

Before you start

  • Make sure the JavaScript Debugger plugin is enabled on the Settings/Preferences | Plugins page, tab Installed, see Managing plugins for details.

Set the built-in web server port

  1. Press Ctrl+Alt+S to open the IDE settings and select Build, Execution, Deployment | Debugger.

  2. In the Built-in server area, specify the port where the built-in web server runs. By default this port is set to the default IntelliJ IDEA port 63342 through which IntelliJ IDEA accepts connections from services. You can set the port number to any other value starting from 1024.


  • Suppress calls to the files on the built-in server from other computers or from outside IntelliJ IDEA by clearing the Can accept external connections or Allow unsigned requests checkbox respectively.

  • Choose the way to remove breakpoints, the default setting is Click.

  • On the settings page under the Debugger node, configure advanced debugger options: enable or disable Inline Debugging, specify when you want to see tooltips with object values and expressions evaluation results, and so on.

  • Click JavaScript under the Data Views node and on the JavaScript page that opens, specify the following:

    • Whether you want object node properties to be shown. If so, specify the properties. Use Icons general add  and Icons general remove to manage the list of properties.

Starting a debugging session with your default Chrome user data

You may notice that your debugging session starts in a new window with a custom Chrome user data instead of your default one. As a result, the window looks unusual, for example, your bookmarks, the browser history, and the extensions are missing, which altogether breaks your development experience. That happens because IntelliJ IDEA uses Chrome Debugging Protocol and runs Chrome with the --remote-debugging-port option. However, if Chrome is already started, a debugging port can't be opened for any new or existing Chrome instance that has the same user data. Therefore, when Chrome Debugging Protocol is used, IntelliJ IDEA always starts a debugging session with in a new window with a custom user data.

To open a new Chrome instance with your familiar look-and-feel, configure Chrome in IntelliJ IDEA to start with your user data. In this case, before starting a debugging session, always make sure that Chrome is not already running with your user data. Otherwise IntelliJ IDEA still launches another instance of Chrome with your user data but is unable to open a debugging port for it. As a result, IntelliJ IDEA debugger fails to connect to the application in the new Chrome instance and the debugging session does not start.

Configure Chrome in IntelliJ IDEA to start with your Chrome user data

  1. Save your Chrome user data anywhere on your machine.

  2. Press Ctrl+Alt+S to open the IDE settings and select Tools | Web Browsers.

  3. To create a new Chrome configuration, click Add. A new item appears in the list. In the Path field, specify the path to the Chrome installation folder.

  4. Select the new configuration and click Edit. The Chrome Settings dialog opens.

  5. Select the Use custom user data directory checkbox and specify the path to your user data directory in the IntelliJ IDEA settings.

  6. Mark your Chrome browser configuration default as described in Web Browsers, and don't forget to choose Default from the Browser list when creating a run/debug configuration.

Last modified: 02 August 2022