diff --git a/mozilla/embedding/browser/activex/src/install/client-win b/mozilla/embedding/browser/activex/src/install/client-win
new file mode 100644
index 00000000000..fa26ec5e6e4
--- /dev/null
+++ b/mozilla/embedding/browser/activex/src/install/client-win
@@ -0,0 +1,21 @@
+;
+; This is the ActiveX client supplemental file read while creating the embedding dist.
+;
+; Copy it to embedding/dist so that additional files here are picked up in addition to
+; those in basebrowser-win.
+
+; MathML
+components\ucvmath.dll
+res\mathml.css
+res\dtd\mathml.dtd
+res\entityTables\mathml20.properties
+res\fonts\mathfont.properties
+res\fonts\mathfontCMEX10.properties
+res\fonts\mathfontCMSY10.properties
+res\fonts\mathfontMath1.properties
+res\fonts\mathfontMath2.properties
+res\fonts\mathfontMath4.properties
+res\fonts\mathfontMTExtra.properties
+res\fonts\mathfontPUA.properties
+res\fonts\mathfontSymbol.properties
+