diff --git a/nixos/doc/manual/configuration/xfce.xml b/nixos/doc/manual/configuration/xfce.xml
index ebf1f493c5ce..abcf5f648a48 100644
--- a/nixos/doc/manual/configuration/xfce.xml
+++ b/nixos/doc/manual/configuration/xfce.xml
@@ -16,11 +16,11 @@
   effects, some example settings:
 <programlisting>
 <link linkend="opt-services.picom.enable">services.picom</link> = {
-  <link linkend="opt-services.picom.enable">enable</link>          = true;
-  <link linkend="opt-services.picom.fade">fade</link>            = true;
-  <link linkend="opt-services.picom.inactiveOpacity">inactiveOpacity</link> = "0.9";
-  <link linkend="opt-services.picom.shadow">shadow</link>          = true;
-  <link linkend="opt-services.picom.fadeDelta">fadeDelta</link>       = 4;
+  <link linkend="opt-services.picom.enable">enable</link> = true;
+  <link linkend="opt-services.picom.fade">fade</link> = true;
+  <link linkend="opt-services.picom.inactiveOpacity">inactiveOpacity</link> = 0.9;
+  <link linkend="opt-services.picom.shadow">shadow</link> = true;
+  <link linkend="opt-services.picom.fadeDelta">fadeDelta</link> = 4;
 };
 </programlisting>
  </para>
diff --git a/nixos/doc/manual/release-notes/rl-2009.xml b/nixos/doc/manual/release-notes/rl-2009.xml
index 78b8eee47efe..ff5c55000e31 100644
--- a/nixos/doc/manual/release-notes/rl-2009.xml
+++ b/nixos/doc/manual/release-notes/rl-2009.xml
@@ -311,6 +311,15 @@ php.override {
      <manvolnum>5</manvolnum></citerefentry> for details.
     </para>
    </listitem>
+   <listitem>
+    <para>
+      In the <literal>picom</literal> module, several options that accepted
+      floating point numbers encoded as strings (for example
+      <xref linkend="opt-services.picom.activeOpacity"/>) have been changed
+      to the (relatively) new native <literal>float</literal> type. To migrate
+      your configuration simply remove the quotes around the numbers.
+    </para>
+   </listitem>
   </itemizedlist>
  </section>