diff --git a/testing/web-platform/meta/MANIFEST.json b/testing/web-platform/meta/MANIFEST.json
index 8a208c9ebb68..473f8c2adaa7 100644
--- a/testing/web-platform/meta/MANIFEST.json
+++ b/testing/web-platform/meta/MANIFEST.json
@@ -405905,30 +405905,6 @@
      {}
     ]
    ],
-   "webdriver/tests/get_element_attribute.py": [
-    [
-     "/webdriver/tests/get_element_attribute.py",
-     {}
-    ]
-   ],
-   "webdriver/tests/get_element_property.py": [
-    [
-     "/webdriver/tests/get_element_property.py",
-     {}
-    ]
-   ],
-   "webdriver/tests/get_element_rect.py": [
-    [
-     "/webdriver/tests/get_element_rect.py",
-     {}
-    ]
-   ],
-   "webdriver/tests/get_element_tag_name.py": [
-    [
-     "/webdriver/tests/get_element_tag_name.py",
-     {}
-    ]
-   ],
    "webdriver/tests/get_window_rect.py": [
     [
      "/webdriver/tests/get_window_rect.py",
@@ -405959,6 +405935,36 @@
      {}
     ]
    ],
+   "webdriver/tests/state/get_element_attribute.py": [
+    [
+     "/webdriver/tests/state/get_element_attribute.py",
+     {}
+    ]
+   ],
+   "webdriver/tests/state/get_element_property.py": [
+    [
+     "/webdriver/tests/state/get_element_property.py",
+     {}
+    ]
+   ],
+   "webdriver/tests/state/get_element_rect.py": [
+    [
+     "/webdriver/tests/state/get_element_rect.py",
+     {}
+    ]
+   ],
+   "webdriver/tests/state/get_element_tag_name.py": [
+    [
+     "/webdriver/tests/state/get_element_tag_name.py",
+     {}
+    ]
+   ],
+   "webdriver/tests/state/is_element_selected.py": [
+    [
+     "/webdriver/tests/state/is_element_selected.py",
+     {}
+    ]
+   ],
    "webdriver/tests/state/text/get_text.py": [
     [
      "/webdriver/tests/state/text/get_text.py",
@@ -412963,7 +412969,7 @@
    "testharness"
   ],
   "XMLHttpRequest/abort-after-send.htm": [
-   "0491be6129a5d78a55d043f3dc0b5322611b9485",
+   "1ec12c1906dd99e9c048925c560ce1b9ac1a4410",
    "testharness"
   ],
   "XMLHttpRequest/abort-after-stop.htm": [
@@ -597643,7 +597649,7 @@
    "testharness"
   ],
   "intersection-observer/timestamp.html": [
-   "b9bf8d472d7751ec4a1ebee925d12668bedeee7a",
+   "0d57a6abc3c3056f921401f629ab231c458cf4cb",
    "testharness"
   ],
   "intersection-observer/unclipped-root.html": [
@@ -626298,22 +626304,6 @@
    "5ba51b660c7203bba3ada597c2f56fe094358e1f",
    "wdspec"
   ],
-  "webdriver/tests/get_element_attribute.py": [
-   "6a42b84f48d90cdbe6dba4485f9d368e6b02418d",
-   "wdspec"
-  ],
-  "webdriver/tests/get_element_property.py": [
-   "74009c12bf986a0d1e4ab9bc9f60de14cbbb474e",
-   "wdspec"
-  ],
-  "webdriver/tests/get_element_rect.py": [
-   "32342cba9762737de327cc8f717fb8316f8f5083",
-   "wdspec"
-  ],
-  "webdriver/tests/get_element_tag_name.py": [
-   "63aa430693c8dbadb600f60516990c3c6c5f4933",
-   "wdspec"
-  ],
   "webdriver/tests/get_window_rect.py": [
    "2d4c13edc4e659af864750d0341c06ff969a687f",
    "wdspec"
@@ -626342,6 +626332,26 @@
    "da39a3ee5e6b4b0d3255bfef95601890afd80709",
    "support"
   ],
+  "webdriver/tests/state/get_element_attribute.py": [
+   "7d531acbe34c1f48f519158f813c5bce88b33259",
+   "wdspec"
+  ],
+  "webdriver/tests/state/get_element_property.py": [
+   "2d4e145cd55c6ee0ed69c617c77975e295e56119",
+   "wdspec"
+  ],
+  "webdriver/tests/state/get_element_rect.py": [
+   "9bbc24b6ce5c386aa8a71efeb2f9d6e5792f81d8",
+   "wdspec"
+  ],
+  "webdriver/tests/state/get_element_tag_name.py": [
+   "ed23abfb5a1e9d3afdf168c722e7b64827c176ec",
+   "wdspec"
+  ],
+  "webdriver/tests/state/is_element_selected.py": [
+   "77b93dd58e0fb4f504c94bc39013d6ada59126bc",
+   "wdspec"
+  ],
   "webdriver/tests/state/text/__init__.py": [
    "da39a3ee5e6b4b0d3255bfef95601890afd80709",
    "support"
diff --git a/testing/web-platform/tests/webdriver/tests/state/is_element_selected.py b/testing/web-platform/tests/webdriver/tests/state/is_element_selected.py
new file mode 100644
index 000000000000..c82f26fa912a
--- /dev/null
+++ b/testing/web-platform/tests/webdriver/tests/state/is_element_selected.py
@@ -0,0 +1,180 @@
+from tests.support.asserts import assert_error, assert_dialog_handled, assert_success
+from tests.support.inline import inline
+from tests.support.fixtures import create_dialog
+
+
+alert_doc = inline("<script>window.alert()</script>")
+check_doc = inline("<input id=checked type=checkbox checked/><input id=notChecked type=checkbox/>")
+option_doc = inline("""<select>
+                        <option id=notSelected>r-</option>
+                        <option id=selected selected>r+</option>
+                       </select>
+                    """)
+
+
+# 13.1 Is Element Selected
+
+def test_no_browsing_context(session, create_window):
+    # 13.1 step 1
+    session.window_handle = create_window()
+    session.close()
+
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id="foo"))
+
+    assert_error(result, "no such window")
+
+
+def test_handle_prompt_dismiss(new_session):
+    # 13.1 step 2
+    _, session = new_session({"alwaysMatch": {"unhandledPromptBehavior": "dismiss"}})
+    session.url = inline("<input id=foo>")
+
+    create_dialog(session)("alert", text="dismiss #1", result_var="dismiss1")
+
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id="foo"))
+
+    assert_success(result, "foo")
+    assert_dialog_handled(session, "dismiss #1")
+
+    create_dialog(session)("confirm", text="dismiss #2", result_var="dismiss2")
+
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id="foo"))
+
+    assert_success(result, "foo")
+    assert_dialog_handled(session, "dismiss #2")
+
+    create_dialog(session)("prompt", text="dismiss #3", result_var="dismiss3")
+
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id="foo"))
+
+    assert_success(result, "foo")
+    assert_dialog_handled(session, "dismiss #3")
+
+
+def test_handle_prompt_accept(new_session):
+    # 13.1 step 2
+    _, session = new_session({"alwaysMatch": {"unhandledPromptBehavior": "accept"}})
+    session.url = inline("<input id=foo>")
+
+    create_dialog(session)("alert", text="dismiss #1", result_var="dismiss1")
+
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id="foo"))
+
+    assert_success(result, "foo")
+    assert_dialog_handled(session, "dismiss #1")
+
+    create_dialog(session)("confirm", text="dismiss #2", result_var="dismiss2")
+
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id="foo"))
+
+    assert_success(result, "foo")
+    assert_dialog_handled(session, "dismiss #2")
+
+    create_dialog(session)("prompt", text="dismiss #3", result_var="dismiss3")
+
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id="foo"))
+
+    assert_success(result, "foo")
+    assert_dialog_handled(session, "dismiss #3")
+
+
+def test_handle_prompt_missing_value(session, create_dialog):
+    # 13.1 step 2
+    session.url = inline("<input id=foo>")
+
+    create_dialog(session)("alert", text="dismiss #1", result_var="dismiss1")
+
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id="foo"))
+
+    assert_error(result, "unexpected alert open")
+    assert_dialog_handled(session, "dismiss #1")
+
+    create_dialog(session)("confirm", text="dismiss #2", result_var="dismiss2")
+
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id="foo"))
+
+    assert_error(result, "unexpected alert open")
+    assert_dialog_handled(session, "dismiss #2")
+
+    create_dialog(session)("prompt", text="dismiss #3", result_var="dismiss3")
+
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id="foo"))
+
+    assert_error(result, "unexpected alert open")
+    assert_dialog_handled(session, "dismiss #3")
+
+
+def test_element_stale(session):
+    # 13.1 step 4
+    session.url = check_doc
+    element = session.find.css("#checked", all=False)
+    session.refresh()
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id=element.id))
+
+    assert_error(result, "stale element reference")
+
+
+def test_element_checked(session):
+    # 13.1 step 5
+    session.url = check_doc
+    element = session.find.css("#checked", all=False)
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id=element.id))
+
+    assert_success(result, True)
+
+
+def test_checkbox_not_selected(session):
+    # 13.1 step 5
+    session.url = check_doc
+    element = session.find.css("#notChecked", all=False)
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id=element.id))
+
+    assert_success(result, False)
+
+
+def test_element_selected(session):
+    # 13.1 step 5
+    session.url = option_doc
+    element = session.find.css("#selected", all=False)
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id=element.id))
+
+    assert_success(result, True)
+
+
+def test_element_not_selected(session):
+    # 13.1 step 5
+    session.url = option_doc
+    element = session.find.css("#notSelected", all=False)
+    result = session.transport.send("GET", "session/{session_id}/element/{element_id}/selected"
+                                    .format(session_id=session.session_id,
+                                            element_id=element.id))
+
+    assert_success(result, False)