docs: fix typos. [skip ci]
@@ -73,11 +73,11 @@ the <var><a href="mod_proxy.html#upgrade">upgrade</a></var> parameter in the
<directive type="ProxyPass" module="mod_proxy">ProxyPass</directive>
directive to some custom protocol name.
Special <code>upgrade=NONE</code> and <code>upgrade=ANY</code> values may be used for
-testing/forcing the upgrade but they are <strong>not recommended</strong> for production for
+testing/forcing the upgrade but they are <strong>not recommended</strong> in production for
security reasons.
-<code>NONE</code> means that the check for the header is omitted but still the upgrade to
-WebSocket still happens.
-<code>ANY</code> means that the upgrade will happen with any protocol asked by the client.
+<code>NONE</code> means that the check for the header is omitted but still the upgrade/tunneling to
+WebSocket always happens.
+<code>ANY</code> means that the upgrade/tunneling will happen using any protocol asked by the client.
</p>
</summary>
