To test HTTPS applications using an external Chrome browser with Burp Suite, you must install Burp's Certificate Authority (CA) certificate. This allows Chrome to trust the traffic proxied through Burp, preventing security warnings and allowing you to intercept encrypted requests. Step 1: Download the Burp CA Certificate
Before importing the certificate into Chrome, you must first download or export it from Burp Suite. Installing Burp's CA certificate - PortSwigger how to download burp certificate for chrome