diff --git a/mozilla/layout/generic/crashtests/431260-1.html b/mozilla/layout/generic/crashtests/431260-1.html
new file mode 100644
index 00000000000..0e4bfb812e4
--- /dev/null
+++ b/mozilla/layout/generic/crashtests/431260-1.html
@@ -0,0 +1,34 @@
+<html class="reftest-wait"><head><style>
+title::first-letter {font-size:600%;}
+</style><title style="display: table-column-group; position: absolute;">
+mmmmmmmmmmmmmmm mmmmmmmmmmmmmmmm mmmmmmmmmm mmmmmmmmmmmmmmmmmmmmm mmmmmmmmmm6mmmmm
+mmmm mmmmMmmmmmmmm=mmmmmmmmm mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm
+mmmmmmmmmmmmmmmmmmm mmmmmmmmmmmmmmm mmmmmmmm mmmmm mmmmmmmmmmmmmm mmmmmmmmmmmmmmmmmmm mmmmmmmmmmmmmmm mmmmmmmm mmmmmmm
+&#1593m
+mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm 
+mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm 
+mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm 
+mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm 
+mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm 
+mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm 
+mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm 
+mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm 
+mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm 
+mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm 
+mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm 
+mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm mmmmm 
+&#1593m н&#1593m&#1593m&#1593mннн&#1593mн&#1593mн&#1593mн&#1593mн&#1593mн&#1593mн&#1593
+&#1593m н&#1593m&#1593m&#1593mннн&#1593mн&#1593mн&#1593mн&#1593mн&#1593mн&#1593mн&#1593
+</title></head>
+<script>
+function innerhtml(i){
+  if (i > 0) {
+    document.documentElement.innerHTML = document.documentElement.innerHTML;
+    setTimeout(innerhtml,0,i-1);
+  } else {
+    document.documentElement.removeAttribute("class");
+  }
+}
+setTimeout(innerhtml,0,30);
+</script>
+</html>
diff --git a/mozilla/layout/generic/crashtests/431260-2.html b/mozilla/layout/generic/crashtests/431260-2.html
new file mode 100644
index 00000000000..7fc9204c20a
--- /dev/null
+++ b/mozilla/layout/generic/crashtests/431260-2.html
@@ -0,0 +1,26 @@
+<html class="reftest-wait"><head><style>
+  title::first-letter {}
+  title {
+    display: inline;
+    float: left;
+    font-size: 16px;
+  }
+</style>
+<script>
+  function boom() {
+    document.documentElement.innerHTML = document.documentElement.innerHTML;
+    document.documentElement.removeAttribute("class");
+  }
+</script>
+<title>
+a
+b
+&#1593
+c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c
+c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c
+c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c
+</title></head>
+<script>
+setTimeout(boom, 0);
+</script>
+</html>
diff --git a/mozilla/layout/generic/crashtests/crashtests.list b/mozilla/layout/generic/crashtests/crashtests.list
index cb7e6ba947c..cd552e134f9 100644
--- a/mozilla/layout/generic/crashtests/crashtests.list
+++ b/mozilla/layout/generic/crashtests/crashtests.list
@@ -140,5 +140,7 @@ load 421671.html
 load 422283-1.html
 load 422301-1.html
 load 425253-1.html
+load 431260-1.html
+load 431260-2.html
 load 445288.html
 load 477928.html
