First create a Certs folder in any Drive other than C:/
Install OpenSSL if you don’t have it (it’s available for Windows, macOS, and Linux)
Create a configuration file for OpenSSL to include the SAN. Create a file named san.cnf with the following content:
[req]

distinguished_name = req_distinguished_name

x509_extensions = v3_req

prompt = no

[req_distinguished_name]

CN = localhost

[v3_req]

subjectAltName = @alt_names

[alt_names]

DNS.1 = localhost

IP.1 = 127.0.0.1

Run the following OpenSSL command to generate a new key and certificate:
openssl req -x509 -newkey rsa:2048 -nodes -days 365 -keyout localhost.key -out localhost.pem -config san.cnf

In VS code editsettings.json paste this

"liveServer.settings.https": {
    "enable": true,
    "cert": "D:/Certs/localhost.pem",
    "key": "D:/Certs/localhost.key",
    "passphrase": ""
}

3. Trust the Certificate

Since this is a self-signed certificate, you need to tell your browser to trust it:

• On Windows:

  1. Double-click localhost.pem to open it in the Certificate Viewer.

  2. Click "Install Certificate" and choose to install it in the "Trusted Root Certification Authorities" store.

  3. Restart your browser.

• On macOS:

  1. Open Keychain Access.

  2. Drag localhost.pem into the "System" keychain.

  3. Double-click the certificate, expand "Trust," and set "When using this certificate" to "Always Trust."

  4. Restart your browser.

• On Linux:

  1. Add the certificate to your system’s trusted certificates (this varies by distribution; for Ubuntu, you might use update-ca-certificates).

  2. Restart your browser.

4. Restart Live Server

• In Visual Studio Code, stop the Live Server (if it’s running).

• Restart it by opening your project and clicking "Go Live" again. The server should now use the updated certificate.

5. Test in Browser

• Open https://127.0.0.1:5500 (or the port Live Server is using) in your browser.

• If the certificate is correctly configured and trusted, you should no longer see the "Your connection is not private" error.

6. Alternative: Use localhost Instead of 127.0.0.1

• If your certificate’s CN or SAN includes localhost but not 127.0.0.1, try accessing your site via https://localhost:5500 instead of https://127.0.0.1:5500. Browsers are often more lenient with localhost for local development.