--- a/layout/base/tests/marionette/selection.py
+++ b/layout/base/tests/marionette/selection.py
@@ -1,15 +1,75 @@
 # -*- coding: utf-8 -*-
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 from __future__ import absolute_import
 
+from marionette_driver.marionette import Actions
+
+
+class CaretActions(Actions):
+    def __init__(self, marionette):
+        super(CaretActions, self).__init__(marionette)
+        self._reset_action_chain()
+
+    def _reset_action_chain(self):
+        self.mouse_chain = self.sequence("pointer", "pointer_id", {"pointerType": "mouse"})
+        self.key_chain = self.sequence("key", "keyboard_id")
+
+    def flick(self, element, x1, y1, x2, y2, duration=200):
+        """Perform a flick gesture on the target element.
+
+        :param element: The element to perform the flick gesture on.
+        :param x1: Starting x-coordinate of flick, relative to the top left
+                   corner of the element.
+        :param y1: Starting y-coordinate of flick, relative to the top left
+                   corner of the element.
+        :param x2: Ending x-coordinate of flick, relative to the top left
+                   corner of the element.
+        :param y2: Ending y-coordinate of flick, relative to the top left
+                   corner of the element.
+
+        """
+        rect = element.rect
+        el_x, el_y = rect['x'], rect['y']
+
+        # Add element's (x, y) to make the coordinate relative to the viewport.
+        from_x, from_y = int(el_x + x1), int(el_y + y1)
+        to_x, to_y = int(el_x + x2), int(el_y + y2)
+
+        self.mouse_chain.pointer_move(from_x, from_y) \
+                        .pointer_down() \
+                        .pointer_move(to_x, to_y, duration=duration) \
+                        .pointer_up()
+        return self
+
+    def send_keys(self, keys):
+        """Perform a keyDown and keyUp action for each character in `keys`.
+
+        :param keys: String of keys to perform key actions with.
+
+        """
+        self.key_chain.send_keys(keys)
+        return self
+
+    def perform(self):
+        """Perform the action chain built so far to the server side for execution
+        and clears the current chain of actions.
+
+        Warning: This method performs all the mouse actions before all the key
+        actions!
+
+        """
+        self.mouse_chain.perform()
+        self.key_chain.perform()
+        self._reset_action_chain()
+
 
 class SelectionManager(object):
     '''Interface for manipulating the selection and carets of the element.
 
     We call the blinking cursor (nsCaret) as cursor, and call AccessibleCaret as
     caret for short.
 
     Simple usage example:

--- a/layout/base/tests/marionette/test_accessiblecaret_cursor_mode.py
+++ b/layout/base/tests/marionette/test_accessiblecaret_cursor_mode.py
@@ -6,20 +6,20 @@
 import string
 import sys
 import os
 
 # Add this directory to the import path.
 sys.path.append(os.path.dirname(__file__))
 
 from selection import (
+    CaretActions,
     SelectionManager,
 )
 from marionette_driver.by import By
-from marionette_driver.legacy_actions import Actions
 from marionette_harness.marionette_test import (
     MarionetteTestCase,
     parameterized,
 )
 
 
 class AccessibleCaretCursorModeTestCase(MarionetteTestCase):
     '''Test cases for AccessibleCaret under cursor mode.
@@ -43,17 +43,21 @@ class AccessibleCaretCursorModeTestCase(
         super(AccessibleCaretCursorModeTestCase, self).setUp()
         self.caret_tested_pref = 'layout.accessiblecaret.enabled'
         self.hide_carets_for_mouse = 'layout.accessiblecaret.hide_carets_for_mouse_input'
         self.prefs = {
             self.caret_tested_pref: True,
             self.hide_carets_for_mouse: False,
         }
         self.marionette.set_prefs(self.prefs)
-        self.actions = Actions(self.marionette)
+        self.actions = CaretActions(self.marionette)
+
+    def tearDown(self):
+        self.marionette.actions.release()
+        super(AccessibleCaretCursorModeTestCase, self).tearDown()
 
     def open_test_html(self, test_html):
         self.marionette.navigate(self.marionette.absolute_url(test_html))
 
     @parameterized(_input_id, el_id=_input_id)
     @parameterized(_textarea_id, el_id=_textarea_id)
     @parameterized(_contenteditable_id, el_id=_contenteditable_id)
     def test_move_cursor_to_the_right_by_one_character(self, el_id):
@@ -74,17 +78,17 @@ class AccessibleCaretCursorModeTestCase(
 
         # Tap the front of the input to make first caret appear.
         el.tap(cursor0_x, cursor0_y)
 
         # Move first caret.
         self.actions.flick(el, first_caret0_x, first_caret0_y,
                            first_caret1_x, first_caret1_y).perform()
 
-        self.actions.key_down(content_to_add).key_up(content_to_add).perform()
+        self.actions.send_keys(content_to_add).perform()
         self.assertEqual(target_content, sel.content)
 
     @parameterized(_input_id, el_id=_input_id)
     @parameterized(_textarea_id, el_id=_textarea_id)
     @parameterized(_contenteditable_id, el_id=_contenteditable_id)
     def test_move_cursor_to_end_by_dragging_caret_to_bottom_right_corner(self, el_id):
         self.open_test_html(self._cursor_html)
         el = self.marionette.find_element(By.ID, el_id)
@@ -97,17 +101,17 @@ class AccessibleCaretCursorModeTestCase(
         sel.move_cursor_to_front()
         el.tap(*sel.cursor_location())
 
         # Move first caret to the bottom-right corner of the element.
         src_x, src_y = sel.first_caret_location()
         dest_x, dest_y = el.rect['width'], el.rect['height']
         self.actions.flick(el, src_x, src_y, dest_x, dest_y).perform()
 
-        self.actions.key_down(content_to_add).key_up(content_to_add).perform()
+        self.actions.send_keys(content_to_add).perform()
         self.assertEqual(target_content, sel.content)
 
     @parameterized(_input_id, el_id=_input_id)
     @parameterized(_textarea_id, el_id=_textarea_id)
     @parameterized(_contenteditable_id, el_id=_contenteditable_id)
     def test_move_cursor_to_front_by_dragging_caret_to_front(self, el_id):
         self.open_test_html(self._cursor_html)
         el = self.marionette.find_element(By.ID, el_id)
@@ -127,17 +131,17 @@ class AccessibleCaretCursorModeTestCase(
         sel.move_cursor_to_end()
         sel.move_cursor_by_offset(1, backward=True)
         el.tap(*sel.cursor_location())
         src_x, src_y = sel.first_caret_location()
 
         # Move first caret to the front of the input box.
         self.actions.flick(el, src_x, src_y, dest_x, dest_y).perform()
 
-        self.actions.key_down(content_to_add).key_up(content_to_add).perform()
+        self.actions.send_keys(content_to_add).perform()
         self.assertEqual(target_content, sel.content)
 
     def test_caret_not_appear_when_typing_in_scrollable_content(self):
         self.open_test_html(self._cursor_html)
         el = self.marionette.find_element(By.ID, self._input_id)
         sel = SelectionManager(el)
         content_to_add = '!'
         non_target_content = content_to_add + sel.content + string.ascii_letters
@@ -176,17 +180,17 @@ class AccessibleCaretCursorModeTestCase(
         # on the Y-axis.
         el.tap()
         sel.move_cursor_to_front()
         el.tap(*sel.cursor_location())
         x, y = sel.first_caret_location()
 
         # Drag the caret down by 50px, and insert '!'.
         self.actions.flick(el, x, y, x, y + 50).perform()
-        self.actions.key_down(content_to_add).key_up(content_to_add).perform()
+        self.actions.send_keys(content_to_add).perform()
         self.assertNotEqual(non_target_content, sel.content)
 
     @parameterized(_input_id, el_id=_input_id)
     @parameterized(_input_padding_id, el_id=_input_padding_id)
     @parameterized(_textarea_one_line_id, el_id=_textarea_one_line_id)
     @parameterized(_contenteditable_id, el_id=_contenteditable_id)
     def test_caret_not_jump_to_front_when_dragging_up_to_editable_content_boundary(self, el_id):
         self.open_test_html(self._cursor_html)
@@ -198,19 +202,19 @@ class AccessibleCaretCursorModeTestCase(
         # Goal: the cursor position is not changed after dragging the caret down
         # on the Y-axis.
         el.tap()
         sel.move_cursor_to_end()
         sel.move_cursor_by_offset(1, backward=True)
         el.tap(*sel.cursor_location())
         x, y = sel.first_caret_location()
 
-        # Drag the caret up by 50px, and insert '!'.
-        self.actions.flick(el, x, y, x, y - 50).perform()
-        self.actions.key_down(content_to_add).key_up(content_to_add).perform()
+        # Drag the caret up by 40px, and insert '!'.
+        self.actions.flick(el, x, y, x, y - 40).perform()
+        self.actions.send_keys(content_to_add).perform()
         self.assertNotEqual(non_target_content, sel.content)
 
     def test_drag_caret_from_front_to_end_across_columns(self):
         self.open_test_html('layout/test_carets_columns.html')
         el = self.marionette.find_element(By.ID, 'columns-inner')
         sel = SelectionManager(el)
         content_to_add = '!'
         target_content = sel.content + content_to_add
@@ -226,17 +230,17 @@ class AccessibleCaretCursorModeTestCase(
         sel.move_cursor_to_front()
         el.tap(*sel.cursor_location())
         src_x, src_y = sel.first_caret_location()
         dest_x, dest_y = el.rect['width'], el.rect['height']
 
         # Drag the first caret to the bottom-right corner of the element.
         self.actions.flick(el, src_x, src_y, dest_x, dest_y).perform()
 
-        self.actions.key_down(content_to_add).key_up(content_to_add).perform()
+        self.actions.send_keys(content_to_add).perform()
         self.assertEqual(target_content, sel.content)
 
     def test_move_cursor_to_front_by_dragging_caret_to_front_br_element(self):
         self.open_test_html(self._cursor_html)
         el = self.marionette.find_element(By.ID, self._contenteditable_id)
         sel = SelectionManager(el)
         content_to_add_1 = '!'
         content_to_add_2 = '\n\n'
@@ -260,10 +264,10 @@ class AccessibleCaretCursorModeTestCase(
         sel.move_cursor_to_end()
         sel.move_cursor_by_offset(1, backward=True)
         el.tap(*sel.cursor_location())
         src_x, src_y = sel.first_caret_location()
 
         # Move first caret to the front of the input box.
         self.actions.flick(el, src_x, src_y, dest_x, dest_y).perform()
 
-        self.actions.key_down(content_to_add_1).key_up(content_to_add_1).perform()
+        self.actions.send_keys(content_to_add_1).perform()
         self.assertEqual(target_content, sel.content)

--- a/layout/base/tests/marionette/test_accessiblecaret_selection_mode.py
+++ b/layout/base/tests/marionette/test_accessiblecaret_selection_mode.py
@@ -6,35 +6,26 @@
 import re
 import sys
 import os
 
 # Add this directory to the import path.
 sys.path.append(os.path.dirname(__file__))
 
 from selection import (
+    CaretActions,
     SelectionManager,
 )
 from marionette_driver.by import By
-from marionette_driver.legacy_actions import Actions
 from marionette_harness.marionette_test import (
     MarionetteTestCase,
     SkipTest,
     parameterized
 )
 
-
-def skip_if_not_rotatable(target):
-    def wrapper(self, *args, **kwargs):
-        if not self.marionette.session_capabilities.get('rotatable'):
-            raise SkipTest('skipping due to device not rotatable')
-        return target(self, *args, **kwargs)
-    return wrapper
-
-
 class AccessibleCaretSelectionModeTestCase(MarionetteTestCase):
     '''Test cases for AccessibleCaret under selection mode.'''
     # Element IDs.
     _input_id = 'input'
     _input_padding_id = 'input-padding'
     _input_size_id = 'input-size'
     _textarea_id = 'textarea'
     _textarea2_id = 'textarea2'
@@ -59,17 +50,21 @@ class AccessibleCaretSelectionModeTestCa
         # Code to execute before every test is running.
         super(AccessibleCaretSelectionModeTestCase, self).setUp()
         self.carets_tested_pref = 'layout.accessiblecaret.enabled'
         self.prefs = {
             'layout.word_select.eat_space_to_next_word': False,
             self.carets_tested_pref: True,
         }
         self.marionette.set_prefs(self.prefs)
-        self.actions = Actions(self.marionette)
+        self.actions = CaretActions(self.marionette)
+
+    def tearDown(self):
+        self.marionette.actions.release()
+        super(AccessibleCaretSelectionModeTestCase, self).tearDown()
 
     def open_test_html(self, test_html):
         self.marionette.navigate(self.marionette.absolute_url(test_html))
 
     def word_offset(self, text, ordinal):
         'Get the character offset of the ordinal-th word in text.'
         tokens = re.split(r'(\S+)', text)         # both words and spaces
         spaces = tokens[0::2]                     # collect spaces at odd indices
@@ -587,18 +582,18 @@ class AccessibleCaretSelectionModeTestCa
 
         # Goal: the selection is not changed after dragging the caret on the
         # Y-axis.
         target_content = words[1]
 
         self.long_press_on_word(el, 1)
         (caret1_x, caret1_y), (caret2_x, caret2_y) = sel.carets_location()
 
-        # Drag the first caret up by 50px.
-        self.actions.flick(el, caret1_x, caret1_y, caret1_x, caret1_y - 50).perform()
+        # Drag the first caret up by 40px.
+        self.actions.flick(el, caret1_x, caret1_y, caret1_x, caret1_y - 40).perform()
         self.assertEqual(target_content, sel.selected_content)
 
         # Drag the second caret down by 50px.
         self.actions.flick(el, caret2_x, caret2_y, caret2_x, caret2_y + 50).perform()
         self.assertEqual(target_content, sel.selected_content)
 
     def test_carets_should_not_appear_when_long_pressing_svg_shapes(self):
         self.open_test_html(self._svg_shapes_html)