To generate the HAR file for Chrome:

1. Go to the page on which you are experiencing the issue.
2. Select More tools > Developer Tools.
3. Select the Network tab.
4. Look for a round 'record' button in the upper left corner of the tab, and make sure it's red. If it is grey, click on it to start the Network recording log (Ctrl+E).
5. Check the Preserve log box.
6. Click the Clear button to clear out any existing logs from the Network tab.
7. Reproduce the issue that you were experiencing.
8. Under the Name column, right-click on any network request within the grid, select Save all as HAR with Content.
9. Save the file. 

To generate the HAR file for Firefox:

1. Go to the page on which you are experiencing the issue.
2. Select the Firefox menu at the top-right of your browser window.
3. Select Web Developer > Network.
4. Click the Network tab in the panel that opens up.
5. Reproduce the activity that was causing the issue in the browser.
6. Right-click anywhere within the grid of network requests, and select Save All As HAR.
7. Save the file. 

To generate the HAR file for Internet Explorer:

1. Go to the page where the issue is occurring.
2. Press F12 on your keyboard (or click the gear icon > F12 Developer Tools)
3. Click the Network tab.
4. Reproduce the issue that you were experiencing before, while the network requests are being recorded.
5. Once done, click the Save button.
6. Save the file. 

To generate the HAR file for Safari:

1. Click on the Develop drop-down menu, and then select Show Web Inspector. If you don’t see the Develop drop-down menu in the menu bar, choose Safari > Preferences, click Advanced, then select Show Develop menu in menu bar.
2. Select the Network tab.
3. Reproduce the issue.
4. Click the download Web Archive icon.
5. Save the file.