diff --git a/mozilla/webtools/bugzilla/.bzrrev b/mozilla/webtools/bugzilla/.bzrrev
index 2a753b0731e..e0c3104715a 100644
--- a/mozilla/webtools/bugzilla/.bzrrev
+++ b/mozilla/webtools/bugzilla/.bzrrev
@@ -1 +1 @@
-9209
\ No newline at end of file
+9210
\ No newline at end of file
diff --git a/mozilla/webtools/bugzilla/.gitrev b/mozilla/webtools/bugzilla/.gitrev
index b918bb06480..509aa29ff1a 100644
--- a/mozilla/webtools/bugzilla/.gitrev
+++ b/mozilla/webtools/bugzilla/.gitrev
@@ -1 +1 @@
-a50e8fd42e682ac115792677104a467445a1c0ad
\ No newline at end of file
+47da91d22f0799f8eedc160909efbbc6feda0afd
\ No newline at end of file
diff --git a/mozilla/webtools/bugzilla/Bugzilla/Template.pm b/mozilla/webtools/bugzilla/Bugzilla/Template.pm
index 7ce1be72bc6..26ef3758596 100644
--- a/mozilla/webtools/bugzilla/Bugzilla/Template.pm
+++ b/mozilla/webtools/bugzilla/Bugzilla/Template.pm
@@ -541,7 +541,9 @@ sub _css_url_rewrite {
     # rewrite relative urls as the unified stylesheet lives in a different
     # directory from the source
     $url =~ s/(^['"]|['"]$)//g;
-    return $url if substr($url, 0, 1) eq '/';
+    if (substr($url, 0, 1) eq '/' || substr($url, 0, 5) eq 'data:') {
+        return 'url(' . $url . ')';
+    }
     return 'url(../../' . dirname($source) . '/' . $url . ')';
 }