diff --git a/accessible/generic/HyperTextAccessible.cpp b/accessible/generic/HyperTextAccessible.cpp
index b4d708720131..ce0f57136070 100644
--- a/accessible/generic/HyperTextAccessible.cpp
+++ b/accessible/generic/HyperTextAccessible.cpp
@@ -1818,8 +1818,16 @@ LayoutDeviceIntRect HyperTextAccessible::GetCaretRect(nsIWidget** aWidget) {
   // the character. This is important for font size transitions, and is
   // necessary because the Gecko caret uses the previous character's size as
   // the user moves forward in the text by character.
+  int32_t caretOffset = CaretOffset();
+  if (NS_WARN_IF(caretOffset == -1)) {
+    // The caret offset will be -1 if this Accessible isn't focused. Note that
+    // the DOM node contaning the caret might be focused, but the Accessible
+    // might not be; e.g. due to an autocomplete popup suggestion having a11y
+    // focus.
+    return LayoutDeviceIntRect();
+  }
   nsIntRect charRect = CharBounds(
-      CaretOffset(), nsIAccessibleCoordinateType::COORDTYPE_SCREEN_RELATIVE);
+      caretOffset, nsIAccessibleCoordinateType::COORDTYPE_SCREEN_RELATIVE);
   if (!charRect.IsEmpty()) {
     caretRect.SetTopEdge(charRect.Y());
   }
diff --git a/accessible/tests/mochitest/events/a11y.ini b/accessible/tests/mochitest/events/a11y.ini
index 746b4cc1725e..74b75785492a 100644
--- a/accessible/tests/mochitest/events/a11y.ini
+++ b/accessible/tests/mochitest/events/a11y.ini
@@ -23,6 +23,7 @@ support-files =
 [test_flush.html]
 [test_focusable_statechange.html]
 [test_focus_aria_activedescendant.html]
+[test_focus_autocomplete.html]
 [test_focus_autocomplete.xhtml]
 # Disabled on Linux and Windows due to frequent failures - bug 695019, bug 890795
 skip-if = os == 'win' || os == 'linux'
diff --git a/accessible/tests/mochitest/events/test_focus_autocomplete.html b/accessible/tests/mochitest/events/test_focus_autocomplete.html
new file mode 100644
index 000000000000..7f5dee75102f
--- /dev/null
+++ b/accessible/tests/mochitest/events/test_focus_autocomplete.html
@@ -0,0 +1,83 @@
+<!doctype html>
+
+<head>
+  <title>Form Autocomplete Tests</title>
+
+  <link rel="stylesheet"
+        href="chrome://mochikit/content/tests/SimpleTest/test.css" />
+
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"></script>
+
+  <script src="../common.js"></script>
+  <script src="../promisified-events.js"></script>
+  <script src="../role.js"></script>
+
+  <script type="application/javascript">
+    const { TestUtils } = ChromeUtils.import(
+      "resource://testing-common/TestUtils.jsm");
+
+    async function waitForFocusOnOptionWithname(name) {
+      let event = await waitForEvent(
+        EVENT_FOCUS,
+        evt => evt.accessible.role == ROLE_COMBOBOX_OPTION
+      );
+      if (!event.accessible.name) {
+        // Sometimes, the name is null for a very short time after the focus
+        // event.
+        await waitForEvent(EVENT_NAME_CHANGE, event.accessible);
+      }
+      is(event.accessible.name, name, "Got focus on option with name " + name);
+    }
+
+    async function doTests() {
+      const input = getNode("input");
+      info("Focusing the input");
+      let focused = waitForEvent(EVENT_FOCUS, input);
+      input.focus();
+      await focused;
+
+      let shown = waitForEvent(EVENT_SHOW, event =>
+        event.accessible.role == ROLE_GROUPING &&
+        event.accessible.firstChild.role == ROLE_COMBOBOX_LIST);
+      info("Pressing ArrowDown to open the popup");
+      synthesizeKey("KEY_ArrowDown");
+      await shown;
+      // The popup still doesn't seem to be ready even once it's fired an a11y
+      // show event!
+      const controller = Cc["@mozilla.org/autocomplete/controller;1"].
+        getService(Ci.nsIAutoCompleteController);
+      info("Waiting for popup to be fully open and ready");
+      await TestUtils.waitForCondition(() => controller.input.popupOpen);
+
+      focused = waitForFocusOnOptionWithname("a");
+      info("Pressing ArrowDown to focus first item");
+      synthesizeKey("KEY_ArrowDown");
+      await focused;
+
+      focused = waitForFocusOnOptionWithname("b");
+      info("Pressing ArrowDown to focus the second item");
+      synthesizeKey("KEY_ArrowDown");
+      await focused;
+
+      focused = waitForEvent(EVENT_FOCUS, input);
+      info("Pressing enter to select the second item");
+      synthesizeKey("KEY_Enter");
+      await focused;
+      is(input.value, "b", "input value filled with second item");
+
+      SimpleTest.finish();
+    }
+
+    SimpleTest.waitForExplicitFinish();
+    addA11yLoadEvent(doTests);
+  </script>
+</head>
+<body>
+  <input id="input" list="list">
+  <datalist id="list">
+    <option id="a" value="a">
+    <option id="b" value="b">
+  </datalist>
+</body>
+</html>
diff --git a/accessible/xul/XULListboxAccessible.cpp b/accessible/xul/XULListboxAccessible.cpp
index 6e48aee6dd77..d17064334e73 100644
--- a/accessible/xul/XULListboxAccessible.cpp
+++ b/accessible/xul/XULListboxAccessible.cpp
@@ -67,10 +67,10 @@ bool XULColumnItemAccessible::DoAction(uint8_t aIndex) const {
 XULListboxAccessible::XULListboxAccessible(nsIContent* aContent,
                                            DocAccessible* aDoc)
     : XULSelectControlAccessible(aContent, aDoc) {
-  nsIContent* parentContent = mContent->GetFlattenedTreeParent();
-  if (parentContent) {
+  dom::Element* parentEl = mContent->GetParentElement();
+  if (parentEl) {
     nsCOMPtr<nsIAutoCompletePopup> autoCompletePopupElm =
-        parentContent->AsElement()->AsAutoCompletePopup();
+        parentEl->AsAutoCompletePopup();
     if (autoCompletePopupElm) mGenericTypes |= eAutoCompletePopup;
   }
 
