diff --git a/mozilla/layout/html/tests/block/bugs/22413.html b/mozilla/layout/html/tests/block/bugs/22413.html
new file mode 100644
index 00000000000..4bbb514584b
--- /dev/null
+++ b/mozilla/layout/html/tests/block/bugs/22413.html
@@ -0,0 +1,38 @@
+<html>
+<body>
+<p>
+This should be the only visible text when the page has loaded, and is with
+M11.
+</p>
+
+<div id="DescriptionText1">
+  <p>This paragraph disappears.</p>
+</div>
+
+<layer>
+  <div id="DescriptionText2">
+    <p>This is visible in M12 -- it should have disappeared.</p>
+  </div>
+</layer>
+
+<div id="DescriptionText3">
+  <layer>
+    <p>This is visible in M12 -- it should have disappeared.</p>
+  <layer>
+</div>
+
+<script LANGUAGE="JavaScript" type="text/javascript">
+  var n = document.getElementById("DescriptionText1");
+  while (n.hasChildNodes())
+    n.removeChild(n.firstChild);
+
+  n = document.getElementById("DescriptionText2");
+  while (n.hasChildNodes())
+    n.removeChild(n.firstChild);
+
+  n = document.getElementById("DescriptionText3");
+  while (n.hasChildNodes())
+    n.removeChild(n.firstChild);
+</script>
+</body>
+</html>
diff --git a/mozilla/layout/html/tests/block/bugs/27211.html b/mozilla/layout/html/tests/block/bugs/27211.html
new file mode 100644
index 00000000000..15b4c9f61e6
--- /dev/null
+++ b/mozilla/layout/html/tests/block/bugs/27211.html
@@ -0,0 +1,21 @@
+<HTML>
+<HEAD>
+<SCRIPT>
+function doit()
+{
+ var span = document.getElementById("foo")
+ document.body.removeChild(span)
+ document.body.appendChild(span)
+}
+</SCRIPT>
+</HEAD>
+<BODY onload='doit()'>
+<SPAN ID=foo>
+one
+<P>
+two
+</P>
+</SPAN>
+<HR>
+</BODY>
+</HTML>
\ No newline at end of file
diff --git a/mozilla/layout/html/tests/block/bugs/39211-a.html b/mozilla/layout/html/tests/block/bugs/39211-a.html
new file mode 100644
index 00000000000..d065a15a97e
--- /dev/null
+++ b/mozilla/layout/html/tests/block/bugs/39211-a.html
@@ -0,0 +1,24 @@
+<html>
+
+<head>
+
+<script>
+
+function m0 ()
+{
+ document.getElementById('ds').innerHTML="<span>text before table <div style='display:block;'>block</div> text after table</span>";
+}
+
+</script>
+</head>
+
+
+<body onload="m0(); m0();">
+
+<div id="ds">
+orig contents of ds
+</div>
+
+</body>
+
+</html>
\ No newline at end of file
diff --git a/mozilla/layout/html/tests/block/bugs/39211-b.html b/mozilla/layout/html/tests/block/bugs/39211-b.html
new file mode 100644
index 00000000000..86e78966f08
--- /dev/null
+++ b/mozilla/layout/html/tests/block/bugs/39211-b.html
@@ -0,0 +1,18 @@
+<html>
+<head>
+<script>
+function doit()
+{
+  var span = document.getElementById("span");
+  var div = span.parentNode;
+  div.removeChild(span);
+  div.appendChild(span);
+}
+</script>
+</head>
+<body onload="doit();">
+<div id="div">
+  <span id="span">here is a span <div style="display:block;">with a block</div> in it</span>
+</div>
+</body>
+</html>
\ No newline at end of file
diff --git a/mozilla/layout/html/tests/block/bugs/39211-c.html b/mozilla/layout/html/tests/block/bugs/39211-c.html
new file mode 100644
index 00000000000..4306bd6e75d
--- /dev/null
+++ b/mozilla/layout/html/tests/block/bugs/39211-c.html
@@ -0,0 +1,32 @@
+<html>
+<head>
+<script>
+function doit()
+{
+  const Elements = ["span", "div", "a", "b", "c", "d", "e"];
+  for (id in Elements) {
+    var child = document.getElementById(Elements[id]);
+    var parent = child.parentNode;
+    var next = child.nextSibling;
+    parent.removeChild(child);
+    parent.insertBefore(child, next);
+  }
+}
+</script>
+</head>
+<body onload="doit();">
+<div id="div">
+  <span id="span">
+    here <span id="a" style="color:green;">is</span> a span
+    <div id="div" style="display:block;">with a <span id="b" style="color:red;">block</span></div>
+    in
+    <span id="c" style="color:blue;">
+      it.
+      <span id="d" style="color:purple;">
+        And here is a much more <span id="e" style="color:pink;">deeply nested span</span>
+      </span>
+    </span>
+  </span>
+</div>
+</body>
+</html>
\ No newline at end of file
diff --git a/mozilla/layout/html/tests/block/bugs/39211.html b/mozilla/layout/html/tests/block/bugs/39211.html
new file mode 100644
index 00000000000..bae76c96a2a
--- /dev/null
+++ b/mozilla/layout/html/tests/block/bugs/39211.html
@@ -0,0 +1,24 @@
+<html>
+
+<head>
+
+<script>
+
+function mO ()
+{
+ document.getElementById('ds').innerHTML="<span>text before table<TABLE BGCOLOR=red><TR><TD>table</TD></TR></TABLE>text after table<\/span>";
+}
+
+</script>
+</head>
+
+
+<body onload="mO();mO();">
+
+<div id="ds">
+orig contents of ds
+</div>
+
+</body>
+
+</html>
\ No newline at end of file
diff --git a/mozilla/layout/html/tests/block/bugs/41521.html b/mozilla/layout/html/tests/block/bugs/41521.html
new file mode 100644
index 00000000000..f0dcdf8f34a
--- /dev/null
+++ b/mozilla/layout/html/tests/block/bugs/41521.html
@@ -0,0 +1,12 @@
+<html>
+<head>
+<script>
+function change()
+{
+  document.getElementById("span").style.fontWeight = "bold";
+}
+</script>
+<body onload="change();">
+<span id="span">This is my happy span. <span style="display: block;">It's got an inline block.</span> It all should be bold.</span>
+</body>
+</html>
\ No newline at end of file
diff --git a/mozilla/layout/html/tests/block/bugs/file_list.txt b/mozilla/layout/html/tests/block/bugs/file_list.txt
index f0829799793..d9a4f530693 100644
--- a/mozilla/layout/html/tests/block/bugs/file_list.txt
+++ b/mozilla/layout/html/tests/block/bugs/file_list.txt
@@ -85,7 +85,14 @@ file:///s:/mozilla/layout/html/tests/block/bugs/17532.html
 file:///s:/mozilla/layout/html/tests/block/bugs/17636.html
 file:///s:/mozilla/layout/html/tests/block/bugs/17844.html
 file:///s:/mozilla/layout/html/tests/block/bugs/22037.html
+file:///s:/mozilla/layout/html/tests/block/bugs/22413.html
+file:///s:/mozilla/layout/html/tests/block/bugs/27211.html
 file:///s:/mozilla/layout/html/tests/block/bugs/36401-a.html
 file:///s:/mozilla/layout/html/tests/block/bugs/36401-b.html
 file:///s:/mozilla/layout/html/tests/block/bugs/36401-c.html
 file:///s:/mozilla/layout/html/tests/block/bugs/36401.html
+file:///s:/mozilla/layout/html/tests/block/bugs/39211.html
+file:///s:/mozilla/layout/html/tests/block/bugs/39211-a.html
+file:///s:/mozilla/layout/html/tests/block/bugs/39211-b.html
+file:///s:/mozilla/layout/html/tests/block/bugs/39211-c.html
+file:///s:/mozilla/layout/html/tests/block/bugs/41521.html
