--- a/layout/base/tests/marionette/test_selectioncarets.py
+++ b/layout/base/tests/marionette/test_selectioncarets.py
@@ -12,16 +12,17 @@ from gestures import long_press_without_
 
 class SelectionCaretsTest(MarionetteTestCase):
     _long_press_time = 1        # 1 second
     _input_selector = (By.ID, 'input')
     _textarea_selector = (By.ID, 'textarea')
     _textarea_rtl_selector = (By.ID, 'textarea_rtl')
     _contenteditable_selector = (By.ID, 'contenteditable')
     _content_selector = (By.ID, 'content')
+    _contenteditable2_selector = (By.ID, 'contenteditable2')
 
     def setUp(self):
         # Code to execute before a tests are run.
         MarionetteTestCase.setUp(self)
         self.actions = Actions(self.marionette)
 
     def openTestHtml(self, enabled=True):
         '''Open html for testing and locate elements, and enable/disable touch
@@ -33,16 +34,17 @@ class SelectionCaretsTest(MarionetteTest
         test_html = self.marionette.absolute_url('test_selectioncarets.html')
         self.marionette.navigate(test_html)
 
         self._input = self.marionette.find_element(*self._input_selector)
         self._textarea = self.marionette.find_element(*self._textarea_selector)
         self._textarea_rtl = self.marionette.find_element(*self._textarea_rtl_selector)
         self._contenteditable = self.marionette.find_element(*self._contenteditable_selector)
         self._content = self.marionette.find_element(*self._content_selector)
+        self._contenteditable2 = self.marionette.find_element(*self._contenteditable2_selector)
 
     def _first_word_location(self, el):
         '''Get the location (x, y) of the first word in el.
 
         Note: this function has a side effect which changes focus to the
         target element el.
 
         '''
@@ -110,27 +112,37 @@ class SelectionCaretsTest(MarionetteTest
 
     def _test_minimum_select_one_character(self, el, assertFunc,
                                            x=None, y=None):
         sel = SelectionManager(el)
         original_content = sel.content
         words = original_content.split()
         self.assertTrue(len(words) >= 1, 'Expect at least one word in the content.')
 
+        # Get the location of the selection carets at the end of the content for
+        # later use.
+        sel.select_all()
+        (_, _), (end_caret_x, end_caret_y) = sel.selection_carets_location()
+        el.tap()
+
         # Goal: Select the first character.
         target_content = original_content[0]
 
         if x and y:
             # If we got x and y from the arguments, use it as a hint of the
             # location of the first word
             pass
         else:
             x, y = self._first_word_location(el)
         self._long_press_to_select(el, x, y)
 
+        # Move the right caret to the end of the content.
+        (caret1_x, caret1_y), (caret2_x, caret2_y) = sel.selection_carets_location()
+        self.actions.flick(el, caret2_x, caret2_y, end_caret_x, end_caret_y).perform()
+
         # Move the right caret to the position of the left caret.
         (caret1_x, caret1_y), (caret2_x, caret2_y) = sel.selection_carets_location()
         self.actions.flick(el, caret2_x, caret2_y, caret1_x, caret1_y,).perform()
 
         assertFunc(target_content, sel.selected_content)
 
     def _test_focus_obtained_by_long_press(self, el1, el2):
         '''Test the focus could be changed from el1 to el2 by long press.
@@ -304,8 +316,16 @@ class SelectionCaretsTest(MarionetteTest
     def test_content_non_editable_focus_obtained_by_long_press_from_textarea(self):
         self.openTestHtml(enabled=True)
         self._test_focus_obtained_by_long_press(self._textarea, self._content)
 
     def test_content_non_editable_focus_obtained_by_long_press_from_contenteditable(self):
         self.openTestHtml(enabled=True)
         self._test_focus_obtained_by_long_press(self._contenteditable, self._content)
 
+    ########################################################################
+    # <div> contenteditable2 test cases with selection carets enabled
+    ########################################################################
+    def test_contenteditable_minimum_select_one_character(self):
+        self.openTestHtml(enabled=True)
+        self._test_minimum_select_one_character(self._contenteditable2, self.assertEqual)
+
+

--- a/testing/marionette/client/marionette/www/test_selectioncarets.html
+++ b/testing/marionette/client/marionette/www/test_selectioncarets.html
@@ -4,20 +4,27 @@
 
 <!DOCTYPE html>
 <html id="html">
   <head>
     <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
     <title>Bug 1019441: Marionette tests for selection carets</title>
   </head>
   <body>
+  <style>
+    *
+    {
+      -moz-user-select:none;
+    }
+  </style>
     <div><input id="input" value="ABC DEF GHI"></div>
     <br />
     <div><textarea id="textarea" rows="4" cols="8">ABC DEF GHI JKL MNO PQR</textarea></div>
     <br />
     <div><textarea dir="rtl" id="textarea_rtl" rows="8" cols="8">موزيلا فيرفكس موزيلا فيرفكس</textarea></div>
     <br />
-    <div style="width: 10em; height: 4em; word-wrap: break-word; overflow: auto;" contenteditable="true" id="contenteditable">ABC DEF GHI</div>
+    <div style="width: 10em; height: 4em; word-wrap: break-word; overflow: auto; -moz-user-select:text" contenteditable="true" id="contenteditable">ABC DEF GHI</div>
     <br />
-    <div style="width: 10em; height: 4em; word-wrap: break-word; overflow: auto;" id="content">ABC DEF GHI</div>
+    <div style="width: 10em; height: 4em; word-wrap: break-word; overflow: auto; -moz-user-select:text" id="content">ABC DEF GHI</div>
     <br />
+    <div style="width: 10em; height: 8em; overflow: auto; -moz-user-select:text" id="contenteditable2" contenteditable="true">First Line<br></br>Second Line<br></br>Third Line</div>
   </body>
 </html>