diff --git a/mercurial/templates/static/mercurial.js b/mercurial/templates/static/mercurial.js
index 4e2fb0ad00a97eaff8bc34d82606afa99a67cfda_bWVyY3VyaWFsL3RlbXBsYXRlcy9zdGF0aWMvbWVyY3VyaWFsLmpz..55543ee545abc53069aa565c1a9f8e88a89a01bf_bWVyY3VyaWFsL3RlbXBsYXRlcy9zdGF0aWMvbWVyY3VyaWFsLmpz 100644
--- a/mercurial/templates/static/mercurial.js
+++ b/mercurial/templates/static/mercurial.js
@@ -327,6 +327,7 @@
     };
 
     xfr.open(method, url);
+    xfr.overrideMimeType("text/xhtml; charset=" + document.characterSet.toLowerCase());
     xfr.send();
     onstart();
     return xfr;