[totem/mallard-documentation] Mention automatic dialog to install missing codecs

[Andre Klapper <aklapper src gnome org>]

commit f8535085b91ffcc2ff194cd9664a3344bc8b653f
Author: Andre Klapper <a9016009 gmx de>
Date:   Sat Jan 12 01:04:03 2019 +0100

    Mention automatic dialog to install missing codecs

 help/C/supported-formats.page | 5 +++++
 1 file changed, 5 insertions(+)
---
diff --git a/help/C/supported-formats.page b/help/C/supported-formats.page
index d0d10143..2ca4db34 100644
--- a/help/C/supported-formats.page
+++ b/help/C/supported-formats.page
@@ -5,6 +5,7 @@
 
   <info>
     <link type="guide" xref="index#troubleshooting"/>
+    <revision pkgversion="3.30" version="0.2" date="2019-01-11" status="draft"/>
     <desc>See what file formats are supported.</desc>
     <credit type="author">
       <name its:translate="no">Marta Bogdanowicz</name>
@@ -25,4 +26,8 @@
   plugins. If certain file formats are not supported, please refer to a support
   forum of your distribution to find out which package to install.</p>
 
+  <note><p>If you try to open a format which is not supported, on many
+  distributions <app>Videos</app> will display a dialog which will allow you
+  to search for missing plugins (codecs) and install them.</p></note>
+
 </page>