An extension that lets you delay the response from specific URLs
Chrome Devtools allows you to throttle network speed across all network requests. However, if you want to slow down a specific URL while leaving others at normal speed, you're out of luck. Use this tool to achieve that. Install and specify the URL with a delay in milliseconds. Whenever the browser requests that URL, the response will be delayed by that amount of time. URLs not matching the ones you enter will behave as they normally would.