Mixed content issue - Content must be served as HTTPS in Laravel

I want to remember this:

When changing from http to https, it's possible to get the problem Mixed content issue - Content must be served as HTTPS.

So, first modify APP_URL in the .env file, if we use the assets helper, this shouldn't give any problem with the URL.

APP_URL=https://mydomain.com

Finally, add the following to the beginning of api.php or web.php:

if (App::environment('production')) {
    URL::forceScheme('https');
}