heroku laravel the content must be served over HTTPS. code example
Example: laravel mixed content error
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');
}