3 files changed, 82 insertions, 16 deletions
diff --git a/editor/libeditor/HTMLEditorDataTransfer.cpp b/editor/libeditor/HTMLEditorDataTransfer.cpp
index b9cd8adb9..ed350c0dd 100644
--- a/editor/libeditor/HTMLEditorDataTransfer.cpp
+++ b/editor/libeditor/HTMLEditorDataTransfer.cpp
@@ -2382,27 +2382,26 @@ HTMLEditor::ReplaceOrphanedStructure(
   }
 
   // If we found substructure, paste it instead of its descendants.
-  // Only replace with the substructure if all the nodes in the list are
-  // descendants.
-  bool shouldReplaceNodes = true;
-  for (uint32_t i = 0; i < aNodeArray.Length(); i++) {
+  // Postprocess list to remove any descendants of this node so that we don't
+  // insert them twice.
+  uint32_t removedCount = 0;
+  uint32_t originalLength = aNodeArray.Length();
+  for (uint32_t i = 0; i < originalLength; i++) {
     uint32_t idx = aStartOrEnd == StartOrEnd::start ?
-      i : (aNodeArray.Length() - i - 1);
+      (i - removedCount) : (originalLength - i - 1);
     OwningNonNull<nsINode> endpoint = aNodeArray[idx];
-    if (!EditorUtils::IsDescendantOf(endpoint, replaceNode)) {
-      shouldReplaceNodes = false;
-      break;
+    if (endpoint == replaceNode ||
+        EditorUtils::IsDescendantOf(endpoint, replaceNode)) {
+      aNodeArray.RemoveElementAt(idx);
+      removedCount++;
     }
   }
 
-  if (shouldReplaceNodes) {
-    // Now replace the removed nodes with the structural parent
-    aNodeArray.Clear();
-    if (aStartOrEnd == StartOrEnd::end) {
-      aNodeArray.AppendElement(*replaceNode);
-    } else {
-      aNodeArray.InsertElementAt(0, *replaceNode);
-    }
+  // Now replace the removed nodes with the structural parent
+  if (aStartOrEnd == StartOrEnd::end) {
+    aNodeArray.AppendElement(*replaceNode);
+  } else {
+    aNodeArray.InsertElementAt(0, *replaceNode);
   }
 }
 
diff --git a/editor/libeditor/tests/mochitest.ini b/editor/libeditor/tests/mochitest.ini
index 9aafa0ac2..4df3f606b 100644
--- a/editor/libeditor/tests/mochitest.ini
+++ b/editor/libeditor/tests/mochitest.ini
@@ -217,6 +217,9 @@ skip-if = toolkit == 'android'
 [test_bug1258085.html]
 [test_bug1268736.html]
 [test_bug1270235.html]
+[test_bug1306532.html]
+subsuite = clipboard
+skip-if = toolkit == 'android'
 [test_bug1310912.html]
 skip-if = toolkit == 'android' # bug 1315898
 [test_bug1314790.html]
diff --git a/editor/libeditor/tests/test_bug1306532.html b/editor/libeditor/tests/test_bug1306532.html
new file mode 100644
index 000000000..1d7b3e7af
--- /dev/null
+++ b/editor/libeditor/tests/test_bug1306532.html
@@ -0,0 +1,64 @@
+<!DOCTYPE HTML>
+<html><head>
+<title>Test for bug 1306532</title>
+<style src="/tests/SimpleTest/test.css" type="text/css"></style>
+<script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+<script type="text/javascript" src="/tests/SimpleTest/EventUtils.js"></script>
+
+<script class="testbody" type="application/javascript">
+
+function runTest() {
+  // Copy content from table.
+  var selection = getSelection();
+  var startRange = document.createRange();
+  startRange.setStart(headingone, 0);
+  startRange.setEnd(celltwo, 0);
+  selection.removeAllRanges();
+  selection.addRange(startRange);
+  SpecialPowers.wrap(document).execCommand("copy", false, null);
+
+  // Paste content into "pasteframe"
+  var pasteContainer = pasteframe.contentDocument.body;
+  var pasteRange = pasteframe.contentDocument.createRange();
+  pasteRange.selectNodeContents(pasteContainer);
+  pasteRange.collapse(false);
+  selection.removeAllRanges();
+  selection.addRange(pasteRange);
+  SpecialPowers.wrap(pasteframe.contentDocument).execCommand("paste", false, null);
+
+  is(pasteContainer.querySelector("#headingone").textContent, "Month", "First heading should be 'Month'.");
+  is(pasteContainer.querySelector("#headingtwo").textContent, "Savings", "Second heading should be 'Savings'.");
+  is(pasteContainer.querySelector("#cellone").textContent, "January", "First cell should be 'January'.");
+  is(pasteContainer.querySelector("#celltwo").textContent, "$100", "Second cell should be '$100'.");
+
+  SimpleTest.finish();
+}
+
+SimpleTest.waitForExplicitFinish();
+
+</script>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1306532">Mozilla Bug 1306532</a>
+<p id="display"></p>
+
+<pre id="test">
+</pre>
+
+<div id="container">
+<table border="1">
+  <tr>
+    <th id="headingone">Month</th>
+    <th id="headingtwo">Savings</th>
+  </tr>
+  <tr>
+    <td id="cellone">January</td>
+    <td id="celltwo">$100</td>
+  </tr>
+</table>
+</div>
+
+<iframe onload="runTest();" id="pasteframe" src="data:text/html,<html><body contenteditable='true'>"></iframe>
+
+</body>
+</html>