This article addresses cases where a link opens a new browser tab or window, such as within Java or other plugin templates, which results in no HAR file data capture. The issue occurs because the browser developer tools are scoped to a single tab by default, and the original tab's developer tools do not monitor the new tab's network requests. This article clarifies the two options available for capturing this network traffic.

• Chrome
• Microsoft Edge

Browser developer tools are scoped to a single tab by default. When a link opens a new tab or window, the developer tools from the original tab do not monitor the network requests of the new tab.

There are two options to capture web traffic when a link opens in a new browser tab or window:

Option 1: Enable Auto-open DevTools for Popups

This option is available in Chromium-based browsers.

1. Open the Developer tools from the browser menu.

2. Click the settings (gear) icon to open the Settings panel.

3. Under the Global section, select the Auto-open DevTools for popups checkbox.

4. The browser automatically opens a new Developer Tool window for any new tab or pop-up and captures the network traffic.

Option 2: Use Net-Export

This function captures all web-related network traffic from the browser into a single log file. The Net-Export utility is a pre-built function in Chrome and Edge. Since only web-related network traffic is captured, the file size is much smaller and more relevant than capturing all traffic from the network interfaces.

1. In a new browser tab, navigate to one of the following URLs:

   • For Chrome: chrome://net-export.

   • For Microsoft Edge: edge://net-export.

2. Select the Include raw bytes option.

3. Click Start Logging to Disk.

4. Choose a location and save the JSON log file.

5. Reproduce the issue that needs to be captured.

6. Return to the net-export tab and click Stop Logging.

The generated JSON file can be analyzed by importing it into a network log viewer tool, such as the NetLog Viewer.

NOTE: HAR files and network logs can contain sensitive data, including secrets. Sanitize these files before sharing them.

Related References

• How to Sanitize an HTTP Trace File Automatically
• Sanitizing HTTP Traces