To capture HTTP headers in Chrome:
- Open the developer tools window by pressing CTRL + SHIFT + i
or,
Open the menu on the top-right corner and select More Tools > Developer Tools.
- Click the Network tab.
- Make sure the record button is red and the Preserve log option is checked.
- Once the test is completed, right click on one transaction and select Save all as HAR with content.
Capturing HTTP Headers on Mozilla Firefox:-
- In Firefox, go to the desired website. In this example, it's www.itzecurity.com.
- Click the Menu button and then click Web Developer. The Web Developer menu appears.
- In this menu, select Inspector. The Inspector window appears.
- In this window, select the Network tab.
- In the Network tab, right-click the element you wish to inspect and select Save All As HAR. In this view, the HTTP headers are also visible in the Headers box on the right-hand side.
- Click OK in the dialog box that appears to download the file.