Debug JavaScript code for model-driven apps

Custom logic using JavaScript in model-driven apps are contained within JavaScript web resources. JavaScript web resources provide the libraries that define functions developers register as event handlers.

In a model-driven app viewed within a web browser, you can use developer tools that all modern browsers provide. With these tools you can locate the JavaScript libraries loaded in the model-driven application, set break points and debug your code using common methods.

Model-driven apps viewed using mobile apps on Android, or the Windows desktop app require some additional steps. See:


Because of the way that the libraries are added to the page, you may not easily find the library representing the JavaScript Web resource. These libraries may not be listed in the file list or in the hierarchy of source files.

If you know the name of the JavaScript web resource you want to debug, for Microsoft Edge or Google Chrome sources you can use the Ctrl+P Open file command to locate the file by name and start debugging. If you have an event handler that is causing an error, but you don't know the name of the file, see Identify JavaScript web resource causing error.

More information:

Identify JavaScript web resource causing error

When an event handler causes a script error in a model-driven app, the following dialog appears:

Script error dialog

If you click the Show Details link, you can find the details that include: event name, function name, web resource name, solution name, and publisher name.

Xrm.Navigation.openalertDialog is not a function
Session Id: 53febd7c-3388-4ea5-a195-d84cf5883c30
Correlation Id: d154420e-5999-4250-b140-081f04a8e264
Event Name: onsave
Function Name: Example.formOnSave
Web Resource Name: example_example-form-script
Solution Name: Active
Publisher Name: DefaultPublisherYourOrg
Time: Tue Jan 31 2023 13:36:34 GMT-0800 (Pacific Standard Time)

In this case, the name of the function was incorrect, openalertDialog should be openAlertDialog


You can get the same details on errors using Monitor. More information: Custom script errors.

Debug JavaScript in mobile apps on Android

While using JavaScript web resources for mobile scenarios, you can use your Android device to debug your mobile-specific code and ensure it works as expected.


It is not currently possible to debug devices using iOS.

To debug JavaScript in mobile apps, you must complete the three steps below:

1. Configure your device


Make sure that Discover USB devices is enabled.

2. Configure the mobile application

  1. In the mobile app, go to the list of Power Apps and select on the menu button.

  2. Make sure that the toggle Enable remote debugging for model-driven apps is on.

    Field service mobile app settings

  3. When enabling this option, there's a confirmation dialog. Select Confirm.

    Confirm remote debugging dialog

3. Debug from your development machine

  1. Plug your computer to your Android device.

  2. Open any model-driven app from Power Apps or the Field Service Mobile application

  3. In the edge://inspect/#devices page in your browser, find your organization URL in the Remote Target section.

    Edge DevTools Devices screen

  4. Click on inspect.

More information: Microsoft Edge: Remotely debug Android devices

Debug JavaScript in the Windows desktop app

To debug JavaScript on Windows, you must first install the prerequisite applications.

1. Configure your Windows device

  1. Enable Developer Mode.

    1. Open Windows Settings > Privacy & security > For developers.
    2. Enable Developer Mode.
  2. Enable Device Portal.

    1. Open Windows Settings > Privacy & security > For developers.
    2. Enable Device Portal.
    3. Click Yes to install Windows Developer Mode package when prompted.
    4. Once Device Portal is enabled, note the URL you will use to connect using localhost. On most devices, it's https://localhost:50080
    5. For debugging Power Apps / Field Service Mobile locally, you can continue with Restrict to loopback connections only enabled and Authentication disabled (otherwise you need to set a user password)

    Here's a screenshot summary of the recommended developer settings:

    Enable device portal screen

2. Configure the Windows application

Configure the Power Apps or Field Service Windows desktop app for remote debugging.

Use the Run command (shortcut is Windows + R) and use the following deep link to launch the Windows app with special arguments.

  • Power Apps: ms-apps://?addWebView2AdditionalBrowserArgument=--enable-features=msEdgeDevToolsWdpRemoteDebugging
  • Field Service Mobile: ms-apps-fs://?addWebView2AdditionalBrowserArgument=--enable-features=msEdgeDevToolsWdpRemoteDebugging

3. Debug from Windows

  1. Launch Power Apps or Field Service for Windows.

  2. Open the Microsoft Edge browser and navigate to edge://inspect.

  3. Use the Connect to a remote Windows device section and connect to http://localhost:50080. It takes a few seconds to connect, but you should see the organization URL.

    Inspect in the DevTools screen

  4. Click inspect and the DevTools will open.

JavaScript web resources
Debug a model-driven app with Monitor
Troubleshoot issues in the Power Apps mobile app