diff --git a/4.2.1-User-Scripts.md b/4.2.1-User-Scripts.md
index fadcc4a..2cc1873 100644
--- a/4.2.1-User-Scripts.md
+++ b/4.2.1-User-Scripts.md
@@ -1,4 +1,4 @@
-some scripts... tested in Firemonkey only.<br><br>
+some scripts... tested in [Firemonkey](https://addons.mozilla.org/firefox/addon/firemonkey/) only.<br><br>
 Scripts with `@run-at  document-start` don't work reliable enough with Greasemonkey (as of GM 4.9)!
 
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