should

fetch.bs

@@ -3046,7 +3046,7 @@ boolean <var>credentials</var>, run these steps:
   <p class=note>This connection is obtained but not used directly. It will remain in the
   <a>connection pool</a> for subsequent use.
 
-  <p class=note>The user agent should attempt to initiate a preconnect and perform the full
+  <p class=note>The user agent can attempt to initiate a preconnect and perform the full
   connection handshake (DNS+TCP for HTTP, and DNS+TCP+TLS for HTTPS origins) whenever possible, but
   is allowed to elect to perform a partial handshake (DNS only for HTTP, and DNS or DNS+TCP for
   HTTPS origins), or skip it entirely, due to resource constraints or other reasons.</p>