New email section

_includes/sections/email-warning.html

@@ -0,0 +1,10 @@
+
+<div class="card border-danger">
+  <div class="card-header text-danger"><i class="fas fa-exclamation-circle fa-fw"></i> Warning</div>
+    <div class="card-body">
+      <p class="card-text text-danger">When using end-to-end encryption (E2EE) technology like <a href="https://en.wikipedia.org/wiki/Pretty_Good_Privacy">OpenPGP</a>, email will still have some metadata that is not encrypted in the header of the email. <a href="/providers/email/#metadata">Read more about email metadata.</a></p>
+      <p class="card-text text-danger">OpenPGP also does not support <a href="https://en.wikipedia.org/wiki/Forward_secrecy">Forward secrecy</a>, which means if either your or the recipient's private key is ever stolen, <strong>all</strong> previous messages encrypted with it will be exposed. <a href="/providers/email/#email-encryption">How do I protect my private keys?</a></p>
+      <p class="card-text text-secondary">Rather than use email for prolonged conversations, consider using a medium that does support Forward secrecy.</p>
+      <a href="/software/real-time-communication/" class="btn btn-outline-secondary">Recommended Instant Messengers</a>
+    </div>
+</div>