diff --git a/tools/wiki-user-script.user.js b/tools/wiki-user-script.user.js
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+// ==UserScript==
+// @match https://wiki.humbughq.com/*
+// ==/UserScript==
+
+// Sets a default commit message when editing the Humbug wiki.
+//
+// To install in Chromium 21:
+//   - Close all Chromium windows
+//   - Run chromium --enable-easy-off-store-extension-install
+//   - Navigate to this directory and click the link to this file.
+//
+// May also work in Firefox with Greasemonkey.
+
+(function () {
+    var elem = document.getElementById("logMsg");
+    if (elem != null) {
+        elem.value = "(default commit message)";
+    }
+})();