diff --git a/mozilla/layout/base/crashtests/429865-1.html b/mozilla/layout/base/crashtests/429865-1.html
new file mode 100644
index 00000000000..18b7bcbfb9b
--- /dev/null
+++ b/mozilla/layout/base/crashtests/429865-1.html
@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<html>
+<head>
+<style type="text/css">
+
+body:after { content: '0'; }
+body:first-letter { float: right; }
+
+</style>
+</head>
+
+<body> &#x202E;</body>
+
+</html>
diff --git a/mozilla/layout/base/crashtests/436982-1.html b/mozilla/layout/base/crashtests/436982-1.html
new file mode 100644
index 00000000000..425961b1a7e
--- /dev/null
+++ b/mozilla/layout/base/crashtests/436982-1.html
@@ -0,0 +1,7 @@
+<html xmlns="http://www.w3.org/1999/xhtml"><head>
+<style>
+
+div:first-letter { float: right; }
+
+</style>
+</head><body onload="document.getElementById('a').style.fontFamily = 'a';"><div id="a"> &#x202B;<span></span></div></body></html>
diff --git a/mozilla/layout/base/crashtests/477731-1.html b/mozilla/layout/base/crashtests/477731-1.html
new file mode 100644
index 00000000000..f017fa7cf1c
--- /dev/null
+++ b/mozilla/layout/base/crashtests/477731-1.html
@@ -0,0 +1,6 @@
+<html xmlns="http://www.w3.org/1999/xhtml">
+<head>
+<style type="text/css">body:first-letter { float: left; }</style>
+</head>
+<body style="-moz-column-width: 100000px;" onload="document.body.style.MozColumnWidth='';"> &#x08D9;</body>
+</html>
diff --git a/mozilla/layout/base/crashtests/crashtests.list b/mozilla/layout/base/crashtests/crashtests.list
index 24b402f6822..8baf67a2ba7 100644
--- a/mozilla/layout/base/crashtests/crashtests.list
+++ b/mozilla/layout/base/crashtests/crashtests.list
@@ -111,7 +111,10 @@ load 411870-1.html
 load 412651-1.html
 load 421203-1.xul
 load 425981-1.html
+load 429865-1.html
+load 436982-1.html
 load 466763-1.html
 load 468491-1.html
+load 477731-1.html
 load 488390-1.xhtml
 load 503936-1.html
