diff --git a/doc/flatpak.xml b/doc/flatpak.xml
index e23d957f..08bf54b8 100644
--- a/doc/flatpak.xml
+++ b/doc/flatpak.xml
@@ -607,6 +607,16 @@
               <envar>XDG_DATA_HOME</envar>, flatpak is consulting some of its own.
             </para>
             <variablelist>
+                <varlistentry>
+                    <term><envar>FLATPAK_FANCY_OUTPUT</envar></term>
+                    <listitem><para>
+                        May be set to <literal>0</literal> to avoid fancy
+                        formatting when outputting to a terminal.
+                        This feature is also disabled automatically when
+                        standard output is not a terminal,
+                        or when <envar>G_MESSAGES_DEBUG</envar> is set.
+                    </para></listitem>
+                </varlistentry>
                 <varlistentry>
                     <term><envar>FLATPAK_USER_DIR</envar></term>