diff --git a/doc/go1.17.html b/doc/go1.17.html
index da50935a61..771e2a6c8d 100644
--- a/doc/go1.17.html
+++ b/doc/go1.17.html
@@ -408,7 +408,9 @@ Do not send CLs removing the interior tags from such phrases.
 <dl id="mime"><dt><a href="/pkg/mime/">mime</a></dt>
   <dd>
     <p><!-- CL 305230 -->
-      TODO: <a href="https://golang.org/cl/305230">https://golang.org/cl/305230</a>: support reading shared mime-info database on unix systems
+      On Unix systems, the table of MIME types is now read from the local system's
+      <a href="https://specifications.freedesktop.org/shared-mime-info-spec/shared-mime-info-spec-0.21.html">Shared MIME-info Database</a>
+      when available.
     </p>
   </dd>
 </dl><!-- mime -->
diff --git a/src/mime/type.go b/src/mime/type.go
index 9bbbf216a1..26424339af 100644
--- a/src/mime/type.go
+++ b/src/mime/type.go
@@ -96,9 +96,11 @@ func initMime() {
 // Extensions are looked up first case-sensitively, then case-insensitively.
 //
 // The built-in table is small but on unix it is augmented by the local
-// system's mime.types file(s) if available under one or more of these
-// names:
+// system's MIME-info database or mime.types file(s) if available under one or
+// more of these names:
 //
+//   /usr/local/share/mime/globs2
+//   /usr/share/mime/globs2
 //   /etc/mime.types
 //   /etc/apache2/mime.types
 //   /etc/apache/mime.types