title: Try to use Symfony mailer with Gmail
body: <p>Try to use Symfony mailer with Gmail on my Symfony 5.1 app.</p>
  <p>mailer.yaml:</p>
  <pre><code>framework:
      mailer:
          dsn: '%env(MAILER_DSN)%'
  </code></pre>
  <p>.env:</p>
  <pre><code>MAILER_DSN=gmail+smtp://myadresse@gmail.com:mypassword@localhost
  </code></pre>
  <p>But each time I send a mail, I got:</p>
  <pre><code>Connection could not be established with host &quot;ssl://smtp.gmail.com:465&quot;: stream_socket_client():
  SSL operation failed with code 1. OpenSSL Error messages:
  error:1416F086:SSL routines:tls_process_server_certificate:certificate verify failed
  </code></pre>
  <p>Don't understand why... According to the <a href="https://symfony.com/doc/current/mailer.html" rel="noreferrer">https://symfony.com/doc/current/mailer.html</a> it should work.</p>
  <p>I activated low security app on my Gmail account.</p>
  <p>Thanks for help</p>