Merge staging/1.2.0 changes back to master.
diff --git a/src/chapters/duo-auth.xml b/src/chapters/duo-auth.xml
index d92c469..680e104 100644
--- a/src/chapters/duo-auth.xml
+++ b/src/chapters/duo-auth.xml
@@ -167,7 +167,7 @@
been generated by Duo when you added Guacamole as an "Web SDK"
application, and can be found within the application details in the
"Secret key" field. <emphasis>This value is required and must be EXACTLY
- 20 characters.</emphasis></para>
+ 40 characters.</emphasis></para>
</listitem>
</varlistentry>
</variablelist>