--- a/editor/libeditor/HTMLEditRules.cpp
+++ b/editor/libeditor/HTMLEditRules.cpp
@@ -1951,16 +1951,29 @@ HTMLEditRules::WillDeleteSelection(Selec
                                              &so, address_of(visNode), &eo);
       NS_ENSURE_SUCCESS(rv, rv);
       NS_ENSURE_STATE(mHTMLEditor);
       *aHandled = true;
       rv = mHTMLEditor->DeleteText(nodeAsText, std::min(so, eo),
                                    DeprecatedAbs(eo - so));
       NS_ENSURE_SUCCESS(rv, rv);
 
+      // XXX When Backspace key is pressed, Chromium removes following empty
+      //     text nodes when removing the last character of the non-empty text
+      //     node.  However, Edge never removes empty text nodes even if
+      //     selection is in the following empty text node(s).  For now, we
+      //     should keep our traditional behavior same as Edge for backward
+      //     compatibility.
+      // XXX When Delete key is pressed, Edge removes all preceding empty
+      //     text nodes when removing the first character of the non-empty
+      //     text node.  Chromium removes only selected empty text node and
+      //     following empty text nodes and the first character of the
+      //     non-empty text node.  For now, we should keep our traditional
+      //     behavior same as Chromium for backward compatibility.
+
       DeleteNodeIfCollapsedText(nodeAsText);
 
       rv = InsertBRIfNeeded(aSelection);
       NS_ENSURE_SUCCESS(rv, rv);
 
       // Remember that we did a ranged delete for the benefit of
       // AfterEditInner().
       mDidRangedDelete = true;

--- a/editor/libeditor/WSRunObject.cpp
+++ b/editor/libeditor/WSRunObject.cpp
@@ -478,24 +478,22 @@ WSRunObject::PriorVisibleNode(nsINode* a
 
   WSFragment* run;
   FindRun(aNode, aOffset, &run, false);
 
   // Is there a visible run there or earlier?
   for (; run; run = run->mLeft) {
     if (run->mType == WSType::normalWS) {
       WSPoint point = GetCharBefore(aNode, aOffset);
-      if (point.mTextNode) {
+      // When it's a non-empty text node, return it.
+      if (point.mTextNode && point.mTextNode->Length()) {
         *outVisNode = point.mTextNode;
         *outVisOffset = point.mOffset + 1;
         if (nsCRT::IsAsciiSpace(point.mChar) || point.mChar == nbsp) {
           *outType = WSType::normalWS;
-        } else if (!point.mChar) {
-          // MOOSE: not possible?
-          *outType = WSType::none;
         } else {
           *outType = WSType::text;
         }
         return;
       }
       // If no text node, keep looking.  We should eventually fall out of loop
     }
   }
@@ -522,24 +520,22 @@ WSRunObject::NextVisibleNode(nsINode* aN
 
   WSFragment* run;
   FindRun(aNode, aOffset, &run, true);
 
   // Is there a visible run there or later?
   for (; run; run = run->mRight) {
     if (run->mType == WSType::normalWS) {
       WSPoint point = GetCharAfter(aNode, aOffset);
-      if (point.mTextNode) {
+      // When it's a non-empty text node, return it.
+      if (point.mTextNode && point.mTextNode->Length()) {
         *outVisNode = point.mTextNode;
         *outVisOffset = point.mOffset;
         if (nsCRT::IsAsciiSpace(point.mChar) || point.mChar == nbsp) {
           *outType = WSType::normalWS;
-        } else if (!point.mChar) {
-          // MOOSE: not possible?
-          *outType = WSType::none;
         } else {
           *outType = WSType::text;
         }
         return;
       }
       // If no text node, keep looking.  We should eventually fall out of loop
     }
   }

--- a/editor/libeditor/tests/mochitest.ini
+++ b/editor/libeditor/tests/mochitest.ini
@@ -205,16 +205,17 @@ skip-if = os == 'android'
 subsuite = clipboard
 skip-if = toolkit == 'android'
 [test_bug1248128.html]
 [test_bug1250010.html]
 [test_bug1257363.html]
 [test_bug1248185.html]
 [test_bug1258085.html]
 [test_bug1268736.html]
+[test_bug1315065.html]
 
 [test_CF_HTML_clipboard.html]
 subsuite = clipboard
 [test_composition_event_created_in_chrome.html]
 [test_contenteditable_focus.html]
 [test_dom_input_event_on_htmleditor.html]
 skip-if = toolkit == 'android' # bug 1054087
 [test_dom_input_event_on_texteditor.html]

new file mode 100644
--- /dev/null
+++ b/editor/libeditor/tests/test_bug1315065.html
@@ -0,0 +1,145 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1315065
+-->
+<head>
+  <meta charset="utf-8">
+  <title>Test for Bug 1315065</title>
+  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="application/javascript" src="/tests/SimpleTest/EventUtils.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1315065">Mozilla Bug 1315065</a>
+<div contenteditable><p>abc<br></p></div>
+<script type="application/javascript">
+/** Test for Bug 1315065 **/
+SimpleTest.waitForExplicitFinish();
+SimpleTest.waitForFocus(()=>{
+  var editor = document.getElementsByTagName("div")[0];
+  function initForBackspace(aSelectionCollapsedTo /* = 0 ~ 3 */) {
+    editor.innerHTML = "<p id='p'>abc<br></p>";
+    var p = document.getElementById("p");
+    // FYI: We cannot inserting empty text nodes as expected with
+    //      Node.appendChild() nor Node.insertBefore(). Therefore, let's use
+    //      Range.insertNode() like actual web apps.
+    var selection = window.getSelection();
+    selection.collapse(p, 1);
+    var range = selection.getRangeAt(0);
+    var emptyTextNode3 = document.createTextNode("");
+    range.insertNode(emptyTextNode3);
+    var emptyTextNode2 = document.createTextNode("");
+    range.insertNode(emptyTextNode2);
+    var emptyTextNode1 = document.createTextNode("");
+    range.insertNode(emptyTextNode1);
+    is(p.childNodes.length, 5, "Failed to initialize the editor");
+    is(p.childNodes.item(1), emptyTextNode1, "1st text node should be emptyTextNode1");
+    is(p.childNodes.item(2), emptyTextNode2, "2nd text node should be emptyTextNode2");
+    is(p.childNodes.item(3), emptyTextNode3, "3rd text node should be emptyTextNode3");
+    switch (aSelectionCollapsedTo) {
+      case 0:
+        selection.collapse(p.firstChild, 3); // next to 'c'
+        break;
+      case 1:
+        selection.collapse(emptyTextNode1, 0);
+        break;
+      case 2:
+        selection.collapse(emptyTextNode2, 0);
+        break;
+      case 3:
+        selection.collapse(emptyTextNode3, 0);
+        break;
+      default:
+        ok(false, "aSelectionCollapsedTo is illegal value");
+    }
+  }
+
+  for (var i = 0; i < 4; i++) {
+    const kDescription = i == 0 ? "Backspace from immediately after the last character" :
+                                  "Backspace from " + i + "th empty text node";
+    editor.focus();
+    initForBackspace(i);
+    synthesizeKey("KEY_Backspace", { code: "Backspace" });
+    var p = document.getElementById("p");
+    ok(p, kDescription + ": <p> element shouldn't be removed by Backspace key press");
+    is(p.tagName.toLowerCase(), "p", kDescription + ": <p> element shouldn't be removed by Backspace key press");
+    // When Backspace key is pressed even in empty text nodes, Gecko should not remove empty text nodes for now
+    // because we should keep our traditional behavior (same as Edge) for backward compatibility as far as possible.
+    // In this case, Chromium removes all empty text nodes, but Edge doesn't remove any empty text nodes.
+    is(p.childNodes.length, 5, kDescription + ": <p> should have 5 children after pressing Backspace key");
+    is(p.childNodes.item(0).textContent, "ab", kDescription + ": 'c' should be removed by pressing Backspace key");
+    is(p.childNodes.item(1).textContent, "", kDescription + ": 1st empty text node should not be removed by pressing Backspace key");
+    is(p.childNodes.item(2).textContent, "", kDescription + ": 2nd empty text node should not be removed by pressing Backspace key");
+    is(p.childNodes.item(3).textContent, "", kDescription + ": 3rd empty text node should not be removed by pressing Backspace key");
+    editor.blur();
+  }
+
+  function initForDelete(aSelectionCollapsedTo /* = 0 ~ 3 */) {
+    editor.innerHTML = "<p id='p'>abc<br></p>";
+    var p = document.getElementById("p");
+    // FYI: We cannot inserting empty text nodes as expected with
+    //      Node.appendChild() nor Node.insertBefore(). Therefore, let's use
+    //      Range.insertNode() like actual web apps.
+    var selection = window.getSelection();
+    selection.collapse(p, 0);
+    var range = selection.getRangeAt(0);
+    var emptyTextNode1 = document.createTextNode("");
+    range.insertNode(emptyTextNode1);
+    var emptyTextNode2 = document.createTextNode("");
+    range.insertNode(emptyTextNode2);
+    var emptyTextNode3 = document.createTextNode("");
+    range.insertNode(emptyTextNode3);
+    is(p.childNodes.length, 5, "Failed to initialize the editor");
+    is(p.childNodes.item(0), emptyTextNode3, "1st text node should be emptyTextNode3");
+    is(p.childNodes.item(1), emptyTextNode2, "2nd text node should be emptyTextNode2");
+    is(p.childNodes.item(2), emptyTextNode1, "3rd text node should be emptyTextNode1");
+    switch (aSelectionCollapsedTo) {
+      case 0:
+        selection.collapse(p.childNodes.item(3), 0); // next to 'a'
+        break;
+      case 1:
+        selection.collapse(emptyTextNode1, 0);
+        break;
+      case 2:
+        selection.collapse(emptyTextNode2, 0);
+        break;
+      case 3:
+        selection.collapse(emptyTextNode3, 0);
+        break;
+      default:
+        ok(false, "aSelectionCollapsedTo is illegal value");
+    }
+  }
+
+  for (var i = 0; i < 4; i++) {
+    const kDescription = i == 0 ? "Delete from immediately before the first character" :
+                                  "Delete from " + i + "th empty text node";
+    editor.focus();
+    initForDelete(i);
+    synthesizeKey("KEY_Delete", { code: "Delete" });
+    var p = document.getElementById("p");
+    ok(p, kDescription + ": <p> element shouldn't be removed by Delete key press");
+    is(p.tagName.toLowerCase(), "p", kDescription + ": <p> element shouldn't be removed by Delete key press");
+    if (i == 0) {
+      // If Delete key is pressed in non-empty text node, only the text node should be modified.
+      // This is same behavior as Chromium, but different from Edge.  Edge removes all empty text nodes in this case.
+      is(p.childNodes.length, 5, kDescription + ": <p> should have only 2 children after pressing Delete key (empty text nodes should be removed");
+      is(p.childNodes.item(0).textContent, "", kDescription + ": 1st empty text node should not be removed by pressing Delete key");
+      is(p.childNodes.item(1).textContent, "", kDescription + ": 2nd empty text node should not be removed by pressing Delete key");
+      is(p.childNodes.item(2).textContent, "", kDescription + ": 3rd empty text node should not be removed by pressing Delete key");
+      is(p.childNodes.item(3).textContent, "bc", kDescription + ": 'a' should be removed by pressing Delete key");
+    } else {
+      // If Delete key is pressed in an empty text node, it and following empty text nodes should be removed and the non-empty text node should be modified.
+      // This is same behavior as Chromium, but different from Edge.  Edge removes all empty text nodes in this case.
+      var expectedEmptyTextNodes = 3 - i;
+      is(p.childNodes.length, expectedEmptyTextNodes + 2, kDescription + ": <p> should have only " + i + " children after pressing Delete key (" + i + " empty text nodes should be removed");
+      is(p.childNodes.item(expectedEmptyTextNodes).textContent, "bc", kDescription + ": empty text nodes and 'a' should be removed by pressing Delete key");
+    }
+    editor.blur();
+  }
+  SimpleTest.finish();
+});
+</script>
+</body>
+</html>