diff --git a/doc/install-requirements.xml b/doc/install-requirements.xml
index bbee9d39..d2ac4507 100644
--- a/doc/install-requirements.xml
+++ b/doc/install-requirements.xml
@@ -93,7 +93,7 @@
     <table id="repmgr-compatibility-matrix">
       <title>&repmgr; compatibility matrix</title>
 
-      <tgroup cols="3">
+      <tgroup cols="4">
         <thead>
           <row>
             <entry>