The server-side issues can be diagnosed by seeing the browser's Network logs. You can download these logs from the browser as an HAR file. This page discusses how you can download the logs written in different browsers' Network tab.

Google Chrome

Click icon, and go to More tools > Developer tools.

You can also right-click the page that has issues with it, and select Inspect to open Developer tools.
Click the Network tab.
Enable logs recording (if not enabled ) by clicking the recording button .
Click the icon to delete any log records that may already be present in the Network tab.
Reproduce the issue.
The logs will get recorded in the Network tab.
Export and save the logs as HAR file by clicking the icon on the toolbar.

Firefox

Clickicon.
Select Web Developer > Network.
Reproduce the issue.
Click at the top-right corner in the Network tab.
Select ”Save All As HAR“ to save the logs as HAR file at a specified location.

Safari

By default, the Develop menu in Safari is disabled. You need to enable it first and then next you can save the Console logs. If you've already enabled the Develop menu, you can skip to the Saving the Console logs section to save the logs.

Enabling the Develop menu

Click Safari and then select Preferences...
In the window that opens, click the Advanced tab.
At the bottom of the window, select Show Develop menu in menu bar to enable the Develop menu.

Saving the HAR logs

Click Develop to open a menu.
Select Show Web Inspector.
Click the Network tab.
Reproduce the issue.
Click Export to download the logs as HAR file at a location that you specify.

Firefox

On the top-right corner of the page, click theicon to open the menu.

You can also press F12 key on the keyboard to open tools.
Select F12 Developer Tools.
Click the Network tab.
Click theicon at the toolbar in the Network tab to export the logs as HAR at a specified location.

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