diff --git a/parser/html/nsHtml5Highlighter.cpp b/parser/html/nsHtml5Highlighter.cpp
index 95de9924652c..941b1f7f242d 100644
--- a/parser/html/nsHtml5Highlighter.cpp
+++ b/parser/html/nsHtml5Highlighter.cpp
@@ -152,7 +152,7 @@ nsHtml5Highlighter::Start()
   if (mTabSize > 0) {
     nsString* style = new nsString(NS_LITERAL_STRING("-moz-tab-size: "));
     style->AppendInt(mTabSize);
-    bodyAttrs->addAttribute(nsHtml5AttributeName::ATTR_CLASS, style);
+    bodyAttrs->addAttribute(nsHtml5AttributeName::ATTR_STYLE, style);
   }
 
   Push(nsGkAtoms::body, bodyAttrs);
diff --git a/parser/htmlparser/tests/reftest/bug700260-1-ref.html b/parser/htmlparser/tests/reftest/bug700260-1-ref.html
new file mode 100644
index 000000000000..0ba4495a0950
--- /dev/null
+++ b/parser/htmlparser/tests/reftest/bug700260-1-ref.html
@@ -0,0 +1,3 @@
+    1
+        2
+            3
diff --git a/parser/htmlparser/tests/reftest/bug700260-1.html b/parser/htmlparser/tests/reftest/bug700260-1.html
new file mode 100644
index 000000000000..37d300834751
--- /dev/null
+++ b/parser/htmlparser/tests/reftest/bug700260-1.html
@@ -0,0 +1,3 @@
+	1
+		2
+			3
diff --git a/parser/htmlparser/tests/reftest/reftest.list b/parser/htmlparser/tests/reftest/reftest.list
index 26689eccd5a5..01211aeb9299 100644
--- a/parser/htmlparser/tests/reftest/reftest.list
+++ b/parser/htmlparser/tests/reftest/reftest.list
@@ -15,3 +15,4 @@
 == view-source:bug673094-1.html view-source:bug673094-1-ref.html
 == bug696651-1.html bug696651-1-ref.html
 == bug696651-2.html bug696651-2-ref.html
+== view-source:bug700260-1.html view-source:bug700260-1-ref.html