Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

28 files changed, 3827 insertions, 0 deletions

diff --git a/devtools/client/accessibility/components/AccessibilityPrefs.js b/devtools/client/accessibility/components/AccessibilityPrefs.js
new file mode 100644
index 0000000000..8c5de5f15f
--- /dev/null
+++ b/devtools/client/accessibility/components/AccessibilityPrefs.js
@@ -0,0 +1,109 @@
+/* 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/. */
+"use strict";
+
+// React
+const {
+  createFactory,
+  Component,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+
+const {
+  hr,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+
+loader.lazyGetter(this, "MenuButton", function () {
+  return createFactory(
+    require("resource://devtools/client/shared/components/menu/MenuButton.js")
+  );
+});
+loader.lazyGetter(this, "MenuItem", function () {
+  return createFactory(
+    require("resource://devtools/client/shared/components/menu/MenuItem.js")
+  );
+});
+loader.lazyGetter(this, "MenuList", function () {
+  return createFactory(
+    require("resource://devtools/client/shared/components/menu/MenuList.js")
+  );
+});
+
+const {
+  A11Y_LEARN_MORE_LINK,
+} = require("resource://devtools/client/accessibility/constants.js");
+const { openDocLink } = require("resource://devtools/client/shared/link.js");
+
+const {
+  updatePref,
+} = require("resource://devtools/client/accessibility/actions/ui.js");
+
+const {
+  connect,
+} = require("resource://devtools/client/shared/vendor/react-redux.js");
+const {
+  PREFS,
+} = require("resource://devtools/client/accessibility/constants.js");
+
+class AccessibilityPrefs extends Component {
+  static get propTypes() {
+    return {
+      dispatch: PropTypes.func.isRequired,
+      [PREFS.SCROLL_INTO_VIEW]: PropTypes.bool.isRequired,
+      toolboxDoc: PropTypes.object.isRequired,
+    };
+  }
+
+  togglePref(prefKey) {
+    this.props.dispatch(updatePref(prefKey, !this.props[prefKey]));
+  }
+
+  onPrefClick(prefKey) {
+    this.togglePref(prefKey);
+  }
+
+  onLearnMoreClick() {
+    openDocLink(A11Y_LEARN_MORE_LINK);
+  }
+
+  render() {
+    return MenuButton(
+      {
+        menuId: "accessibility-tree-filters-prefs-menu",
+        toolboxDoc: this.props.toolboxDoc,
+        className: `devtools-button badge toolbar-menu-button prefs`,
+        title: L10N.getStr("accessibility.tree.filters.prefs"),
+      },
+      MenuList({}, [
+        MenuItem({
+          key: "pref-scroll-into-view",
+          checked: this.props[PREFS.SCROLL_INTO_VIEW],
+          className: `pref ${PREFS.SCROLL_INTO_VIEW}`,
+          label: L10N.getStr("accessibility.pref.scroll.into.view.label"),
+          tooltip: L10N.getStr("accessibility.pref.scroll.into.view.title"),
+          onClick: this.onPrefClick.bind(this, PREFS.SCROLL_INTO_VIEW),
+        }),
+        hr({ key: "hr" }),
+        MenuItem({
+          role: "link",
+          key: "accessibility-tree-filters-prefs-menu-help",
+          className: "help",
+          label: L10N.getStr("accessibility.documentation.label"),
+          tooltip: L10N.getStr("accessibility.learnMore"),
+          onClick: this.onLearnMoreClick,
+        }),
+      ])
+    );
+  }
+}
+
+const mapStateToProps = ({ ui }) => ({
+  [PREFS.SCROLL_INTO_VIEW]: ui[PREFS.SCROLL_INTO_VIEW],
+});
+
+// Exports from this module
+module.exports = connect(mapStateToProps)(AccessibilityPrefs);
diff --git a/devtools/client/accessibility/components/AccessibilityRow.js b/devtools/client/accessibility/components/AccessibilityRow.js
new file mode 100644
index 0000000000..ffca5c74ef
--- /dev/null
+++ b/devtools/client/accessibility/components/AccessibilityRow.js
@@ -0,0 +1,328 @@
+/* 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/. */
+"use strict";
+
+/* global gTelemetry, EVENTS */
+
+// React & Redux
+const {
+  Component,
+  createFactory,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  findDOMNode,
+} = require("resource://devtools/client/shared/vendor/react-dom.js");
+const {
+  connect,
+} = require("resource://devtools/client/shared/vendor/react-redux.js");
+
+const TreeRow = require("resource://devtools/client/shared/components/tree/TreeRow.js");
+const AuditFilter = createFactory(
+  require("resource://devtools/client/accessibility/components/AuditFilter.js")
+);
+const AuditController = createFactory(
+  require("resource://devtools/client/accessibility/components/AuditController.js")
+);
+
+// Utils
+const {
+  flashElementOn,
+  flashElementOff,
+} = require("resource://devtools/client/inspector/markup/utils.js");
+const { openDocLink } = require("resource://devtools/client/shared/link.js");
+const {
+  PREFS,
+  VALUE_FLASHING_DURATION,
+  VALUE_HIGHLIGHT_DURATION,
+} = require("resource://devtools/client/accessibility/constants.js");
+
+const nodeConstants = require("resource://devtools/shared/dom-node-constants.js");
+
+// Actions
+const {
+  updateDetails,
+} = require("resource://devtools/client/accessibility/actions/details.js");
+const {
+  unhighlight,
+} = require("resource://devtools/client/accessibility/actions/accessibles.js");
+
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+
+loader.lazyRequireGetter(
+  this,
+  "Menu",
+  "resource://devtools/client/framework/menu.js"
+);
+loader.lazyRequireGetter(
+  this,
+  "MenuItem",
+  "resource://devtools/client/framework/menu-item.js"
+);
+
+const {
+  scrollIntoView,
+} = require("resource://devtools/client/shared/scroll.js");
+
+const JSON_URL_PREFIX = "data:application/json;charset=UTF-8,";
+
+const TELEMETRY_ACCESSIBLE_CONTEXT_MENU_OPENED =
+  "devtools.accessibility.accessible_context_menu_opened";
+const TELEMETRY_ACCESSIBLE_CONTEXT_MENU_ITEM_ACTIVATED =
+  "devtools.accessibility.accessible_context_menu_item_activated";
+
+class HighlightableTreeRowClass extends TreeRow {
+  shouldComponentUpdate(nextProps) {
+    const shouldTreeRowUpdate = super.shouldComponentUpdate(nextProps);
+    if (shouldTreeRowUpdate) {
+      return shouldTreeRowUpdate;
+    }
+
+    if (
+      nextProps.highlighted !== this.props.highlighted ||
+      nextProps.filtered !== this.props.filtered
+    ) {
+      return true;
+    }
+
+    return false;
+  }
+}
+
+const HighlightableTreeRow = createFactory(HighlightableTreeRowClass);
+
+// Component that expands TreeView's own TreeRow and is responsible for
+// rendering an accessible object.
+class AccessibilityRow extends Component {
+  static get propTypes() {
+    return {
+      ...TreeRow.propTypes,
+      dispatch: PropTypes.func.isRequired,
+      toolboxDoc: PropTypes.object.isRequired,
+      scrollContentNodeIntoView: PropTypes.bool.isRequired,
+      highlightAccessible: PropTypes.func.isRequired,
+      unhighlightAccessible: PropTypes.func.isRequired,
+    };
+  }
+
+  componentDidMount() {
+    const {
+      member: { selected, object },
+      scrollContentNodeIntoView,
+    } = this.props;
+    if (selected) {
+      this.unhighlight(object);
+      this.update();
+      this.highlight(
+        object,
+        { duration: VALUE_HIGHLIGHT_DURATION },
+        scrollContentNodeIntoView
+      );
+    }
+
+    if (this.props.highlighted) {
+      this.scrollIntoView();
+    }
+  }
+
+  /**
+   * Update accessible object details that are going to be rendered inside the
+   * accessible panel sidebar.
+   */
+  componentDidUpdate(prevProps) {
+    const {
+      member: { selected, object },
+      scrollContentNodeIntoView,
+    } = this.props;
+    // If row is selected, update corresponding accessible details.
+    if (!prevProps.member.selected && selected) {
+      this.unhighlight(object);
+      this.update();
+      this.highlight(
+        object,
+        { duration: VALUE_HIGHLIGHT_DURATION },
+        scrollContentNodeIntoView
+      );
+    }
+
+    if (this.props.highlighted) {
+      this.scrollIntoView();
+    }
+
+    if (!selected && prevProps.member.value !== this.props.member.value) {
+      this.flashValue();
+    }
+  }
+
+  scrollIntoView() {
+    const row = findDOMNode(this);
+    // Row might not be rendered in the DOM tree if it is filtered out during
+    // audit.
+    if (!row) {
+      return;
+    }
+
+    scrollIntoView(row);
+  }
+
+  update() {
+    const {
+      dispatch,
+      member: { object },
+    } = this.props;
+    if (!object.actorID) {
+      return;
+    }
+
+    dispatch(updateDetails(object));
+    window.emit(EVENTS.NEW_ACCESSIBLE_FRONT_SELECTED, object);
+  }
+
+  flashValue() {
+    const row = findDOMNode(this);
+    // Row might not be rendered in the DOM tree if it is filtered out during
+    // audit.
+    if (!row) {
+      return;
+    }
+
+    const value = row.querySelector(".objectBox");
+
+    flashElementOn(value);
+    if (this._flashMutationTimer) {
+      clearTimeout(this._flashMutationTimer);
+      this._flashMutationTimer = null;
+    }
+    this._flashMutationTimer = setTimeout(() => {
+      flashElementOff(value);
+    }, VALUE_FLASHING_DURATION);
+  }
+
+  /**
+   * Scroll the node that corresponds to a current accessible object into view.
+   * @param   {Object}
+   *          Accessible front that is rendered for this node.
+   *
+   * @returns {Promise}
+   *          Promise that resolves when the node is scrolled into view if
+   *          possible.
+   */
+  async scrollNodeIntoViewIfNeeded(accessibleFront) {
+    if (accessibleFront.isDestroyed()) {
+      return;
+    }
+
+    const domWalker = (await accessibleFront.targetFront.getFront("inspector"))
+      .walker;
+    if (accessibleFront.isDestroyed()) {
+      return;
+    }
+
+    const node = await domWalker.getNodeFromActor(accessibleFront.actorID, [
+      "rawAccessible",
+      "DOMNode",
+    ]);
+    if (!node) {
+      return;
+    }
+
+    if (node.nodeType == nodeConstants.ELEMENT_NODE) {
+      await node.scrollIntoView();
+    } else if (node.nodeType != nodeConstants.DOCUMENT_NODE) {
+      // scrollIntoView method is only part of the Element interface, in cases
+      // where node is a text node (and not a document node) scroll into view
+      // its parent.
+      await node.parentNode().scrollIntoView();
+    }
+  }
+
+  async highlight(accessibleFront, options, scrollContentNodeIntoView) {
+    this.props.dispatch(unhighlight());
+    // If necessary scroll the node into view before showing the accessibility
+    // highlighter.
+    if (scrollContentNodeIntoView) {
+      await this.scrollNodeIntoViewIfNeeded(accessibleFront);
+    }
+
+    this.props.highlightAccessible(accessibleFront, options);
+  }
+
+  unhighlight(accessibleFront) {
+    this.props.dispatch(unhighlight());
+    this.props.unhighlightAccessible(accessibleFront);
+  }
+
+  async printToJSON() {
+    if (gTelemetry) {
+      gTelemetry.keyedScalarAdd(
+        TELEMETRY_ACCESSIBLE_CONTEXT_MENU_ITEM_ACTIVATED,
+        "print-to-json",
+        1
+      );
+    }
+
+    const snapshot = await this.props.member.object.snapshot();
+    openDocLink(
+      `${JSON_URL_PREFIX}${encodeURIComponent(JSON.stringify(snapshot))}`
+    );
+  }
+
+  onContextMenu(e) {
+    e.stopPropagation();
+    e.preventDefault();
+
+    if (!this.props.toolboxDoc) {
+      return;
+    }
+
+    const menu = new Menu({ id: "accessibility-row-contextmenu" });
+    menu.append(
+      new MenuItem({
+        id: "menu-printtojson",
+        label: L10N.getStr("accessibility.tree.menu.printToJSON"),
+        click: () => this.printToJSON(),
+      })
+    );
+
+    menu.popup(e.screenX, e.screenY, this.props.toolboxDoc);
+
+    if (gTelemetry) {
+      gTelemetry.scalarAdd(TELEMETRY_ACCESSIBLE_CONTEXT_MENU_OPENED, 1);
+    }
+  }
+
+  /**
+   * Render accessible row component.
+   * @returns acecssible-row React component.
+   */
+  render() {
+    const { member } = this.props;
+    const props = {
+      ...this.props,
+      onContextMenu: e => this.onContextMenu(e),
+      onMouseOver: () => this.highlight(member.object),
+      onMouseOut: () => this.unhighlight(member.object),
+      key: `${member.path}-${member.active ? "active" : "inactive"}`,
+    };
+
+    return AuditController(
+      {
+        accessibleFront: member.object,
+      },
+      AuditFilter({}, HighlightableTreeRow(props))
+    );
+  }
+}
+
+const mapStateToProps = ({
+  ui: { [PREFS.SCROLL_INTO_VIEW]: scrollContentNodeIntoView },
+}) => ({
+  scrollContentNodeIntoView,
+});
+
+module.exports = connect(mapStateToProps, null, null, { withRef: true })(
+  AccessibilityRow
+);
diff --git a/devtools/client/accessibility/components/AccessibilityRowValue.js b/devtools/client/accessibility/components/AccessibilityRowValue.js
new file mode 100644
index 0000000000..ab631fedb4
--- /dev/null
+++ b/devtools/client/accessibility/components/AccessibilityRowValue.js
@@ -0,0 +1,58 @@
+/* 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/. */
+
+"use strict";
+
+const {
+  Component,
+  createFactory,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  span,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+
+const Badges = createFactory(
+  require("resource://devtools/client/accessibility/components/Badges.js")
+);
+const AuditController = createFactory(
+  require("resource://devtools/client/accessibility/components/AuditController.js")
+);
+
+const {
+  REPS,
+} = require("resource://devtools/client/shared/components/reps/index.js");
+const { Grip } = REPS;
+const Rep = createFactory(REPS.Rep);
+
+class AccessibilityRowValue extends Component {
+  static get propTypes() {
+    return {
+      member: PropTypes.shape({
+        object: PropTypes.object,
+      }).isRequired,
+    };
+  }
+
+  render() {
+    return span(
+      {
+        role: "presentation",
+      },
+      Rep({
+        ...this.props,
+        defaultRep: Grip,
+        cropLimit: 50,
+      }),
+      AuditController(
+        {
+          accessibleFront: this.props.member.object,
+        },
+        Badges()
+      )
+    );
+  }
+}
+
+module.exports = AccessibilityRowValue;
diff --git a/devtools/client/accessibility/components/AccessibilityTree.js b/devtools/client/accessibility/components/AccessibilityTree.js
new file mode 100644
index 0000000000..df67377283
--- /dev/null
+++ b/devtools/client/accessibility/components/AccessibilityTree.js
@@ -0,0 +1,298 @@
+/* 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/. */
+"use strict";
+
+/* global EVENTS */
+
+// React & Redux
+const {
+  Component,
+  createFactory,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  connect,
+} = require("resource://devtools/client/shared/vendor/react-redux.js");
+
+const TreeView = createFactory(
+  require("resource://devtools/client/shared/components/tree/TreeView.js")
+);
+// Reps
+const {
+  MODE,
+} = require("resource://devtools/client/shared/components/reps/index.js");
+
+const {
+  fetchChildren,
+} = require("resource://devtools/client/accessibility/actions/accessibles.js");
+
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+const {
+  isFiltered,
+} = require("resource://devtools/client/accessibility/utils/audit.js");
+const AccessibilityRow = createFactory(
+  require("resource://devtools/client/accessibility/components/AccessibilityRow.js")
+);
+const AccessibilityRowValue = createFactory(
+  require("resource://devtools/client/accessibility/components/AccessibilityRowValue.js")
+);
+const {
+  Provider,
+} = require("resource://devtools/client/accessibility/provider.js");
+
+const {
+  scrollIntoView,
+} = require("resource://devtools/client/shared/scroll.js");
+
+/**
+ * Renders Accessibility panel tree.
+ */
+class AccessibilityTree extends Component {
+  static get propTypes() {
+    return {
+      toolboxDoc: PropTypes.object.isRequired,
+      dispatch: PropTypes.func.isRequired,
+      accessibles: PropTypes.object,
+      expanded: PropTypes.object,
+      selected: PropTypes.string,
+      highlighted: PropTypes.object,
+      filtered: PropTypes.bool,
+      getAccessibilityTreeRoot: PropTypes.func.isRequired,
+      startListeningForAccessibilityEvents: PropTypes.func.isRequired,
+      stopListeningForAccessibilityEvents: PropTypes.func.isRequired,
+      highlightAccessible: PropTypes.func.isRequired,
+      unhighlightAccessible: PropTypes.func.isRequired,
+    };
+  }
+
+  constructor(props) {
+    super(props);
+
+    this.onNameChange = this.onNameChange.bind(this);
+    this.onReorder = this.onReorder.bind(this);
+    this.onTextChange = this.onTextChange.bind(this);
+    this.renderValue = this.renderValue.bind(this);
+    this.scrollSelectedRowIntoView = this.scrollSelectedRowIntoView.bind(this);
+  }
+
+  /**
+   * Add accessibility event listeners that affect tree rendering and updates.
+   */
+  // FIXME: https://bugzilla.mozilla.org/show_bug.cgi?id=1774507
+  UNSAFE_componentWillMount() {
+    this.props.startListeningForAccessibilityEvents({
+      reorder: this.onReorder,
+      "name-change": this.onNameChange,
+      "text-change": this.onTextChange,
+    });
+    window.on(
+      EVENTS.NEW_ACCESSIBLE_FRONT_INSPECTED,
+      this.scrollSelectedRowIntoView
+    );
+    return null;
+  }
+
+  componentDidUpdate(prevProps) {
+    // When filtering is toggled, make sure that the selected row remains in
+    // view.
+    if (this.props.filtered !== prevProps.filtered) {
+      this.scrollSelectedRowIntoView();
+    }
+
+    window.emit(EVENTS.ACCESSIBILITY_INSPECTOR_UPDATED);
+  }
+
+  /**
+   * Remove accessible event listeners.
+   */
+  componentWillUnmount() {
+    this.props.stopListeningForAccessibilityEvents({
+      reorder: this.onReorder,
+      "name-change": this.onNameChange,
+      "text-change": this.onTextChange,
+    });
+
+    window.off(
+      EVENTS.NEW_ACCESSIBLE_FRONT_INSPECTED,
+      this.scrollSelectedRowIntoView
+    );
+  }
+
+  /**
+   * Handle accessible reorder event. If the accessible is cached and rendered
+   * within the accessibility tree, re-fetch its children and re-render the
+   * corresponding subtree.
+   * @param {Object} accessibleFront
+   *        accessible front that had its subtree reordered.
+   */
+  onReorder(accessibleFront) {
+    if (this.props.accessibles.has(accessibleFront.actorID)) {
+      this.props.dispatch(fetchChildren(accessibleFront));
+    }
+  }
+
+  scrollSelectedRowIntoView() {
+    const { treeview } = this.refs;
+    if (!treeview) {
+      return;
+    }
+
+    const treeEl = treeview.treeRef.current;
+    if (!treeEl) {
+      return;
+    }
+
+    const selected = treeEl.ownerDocument.querySelector(
+      ".treeTable .treeRow.selected"
+    );
+    if (selected) {
+      scrollIntoView(selected, { center: true });
+    }
+  }
+
+  /**
+   * Handle accessible name change event. If the name of an accessible changes
+   * and that accessible is cached and rendered within the accessibility tree,
+   * re-fetch its parent's children and re-render the corresponding subtree.
+   * @param {Object} accessibleFront
+   *        accessible front that had its name changed.
+   * @param {Object} parentFront
+   *        optional parent accessible front. Note: if it parent is not
+   *        present, we assume that the top level document's name has changed
+   *        and use accessible walker as a parent.
+   */
+  onNameChange(accessibleFront, parentFront) {
+    const { accessibles, dispatch } = this.props;
+    const accessibleWalkerFront = accessibleFront.getParent();
+    parentFront = parentFront || accessibleWalkerFront;
+
+    if (
+      accessibles.has(accessibleFront.actorID) ||
+      accessibles.has(parentFront.actorID)
+    ) {
+      dispatch(fetchChildren(parentFront));
+    }
+  }
+
+  /**
+   * Handle accessible text change (change/insert/remove) event. If the text of
+   * an accessible changes and that accessible is cached and rendered within the
+   * accessibility tree, re-fetch its children and re-render the corresponding
+   * subtree.
+   * @param  {Object} accessibleFront
+   *         accessible front that had its child text changed.
+   */
+  onTextChange(accessibleFront) {
+    const { accessibles, dispatch } = this.props;
+    if (accessibles.has(accessibleFront.actorID)) {
+      dispatch(fetchChildren(accessibleFront));
+    }
+  }
+
+  renderValue(props) {
+    return AccessibilityRowValue(props);
+  }
+
+  /**
+   * Render Accessibility panel content
+   */
+  render() {
+    const columns = [
+      {
+        id: "default",
+        title: L10N.getStr("accessibility.role"),
+      },
+      {
+        id: "value",
+        title: L10N.getStr("accessibility.name"),
+      },
+    ];
+
+    const {
+      accessibles,
+      dispatch,
+      expanded,
+      selected,
+      highlighted: highlightedItem,
+      toolboxDoc,
+      filtered,
+      getAccessibilityTreeRoot,
+      highlightAccessible,
+      unhighlightAccessible,
+    } = this.props;
+
+    const renderRow = rowProps => {
+      const { object } = rowProps.member;
+      const highlighted = object === highlightedItem;
+      return AccessibilityRow(
+        Object.assign({}, rowProps, {
+          toolboxDoc,
+          highlighted,
+          decorator: {
+            getRowClass() {
+              return highlighted ? ["highlighted"] : [];
+            },
+          },
+          highlightAccessible,
+          unhighlightAccessible,
+        })
+      );
+    };
+    const className = filtered ? "filtered" : undefined;
+
+    return TreeView({
+      ref: "treeview",
+      object: getAccessibilityTreeRoot(),
+      mode: MODE.SHORT,
+      provider: new Provider(accessibles, filtered, dispatch),
+      columns,
+      className,
+      renderValue: this.renderValue,
+      renderRow,
+      label: L10N.getStr("accessibility.treeName"),
+      header: true,
+      expandedNodes: expanded,
+      selected,
+      onClickRow(nodePath, event) {
+        if (event.target.classList.contains("theme-twisty")) {
+          this.toggle(nodePath);
+        }
+
+        this.selectRow(
+          this.rows.find(row => row.props.member.path === nodePath),
+          { preventAutoScroll: true }
+        );
+
+        return true;
+      },
+      onContextMenuTree(e) {
+        // If context menu event is triggered on (or bubbled to) the TreeView, it was
+        // done via keyboard. Open context menu for currently selected row.
+        let row = this.getSelectedRow();
+        if (!row) {
+          return;
+        }
+
+        row = row.getWrappedInstance();
+        row.onContextMenu(e);
+      },
+    });
+  }
+}
+
+const mapStateToProps = ({
+  accessibles,
+  ui: { expanded, selected, highlighted },
+  audit: { filters },
+}) => ({
+  accessibles,
+  expanded,
+  selected,
+  highlighted,
+  filtered: isFiltered(filters),
+});
+// Exports from this module
+module.exports = connect(mapStateToProps)(AccessibilityTree);
diff --git a/devtools/client/accessibility/components/AccessibilityTreeFilter.js b/devtools/client/accessibility/components/AccessibilityTreeFilter.js
new file mode 100644
index 0000000000..90eabd350a
--- /dev/null
+++ b/devtools/client/accessibility/components/AccessibilityTreeFilter.js
@@ -0,0 +1,171 @@
+/* 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/. */
+"use strict";
+
+/* global gTelemetry */
+
+// React
+const {
+  createFactory,
+  Component,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const {
+  div,
+  hr,
+  span,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+
+loader.lazyGetter(this, "MenuButton", function () {
+  return createFactory(
+    require("resource://devtools/client/shared/components/menu/MenuButton.js")
+  );
+});
+loader.lazyGetter(this, "MenuItem", function () {
+  return createFactory(
+    require("resource://devtools/client/shared/components/menu/MenuItem.js")
+  );
+});
+loader.lazyGetter(this, "MenuList", function () {
+  return createFactory(
+    require("resource://devtools/client/shared/components/menu/MenuList.js")
+  );
+});
+
+const actions = require("resource://devtools/client/accessibility/actions/audit.js");
+
+const {
+  connect,
+} = require("resource://devtools/client/shared/vendor/react-redux.js");
+const {
+  FILTERS,
+} = require("resource://devtools/client/accessibility/constants.js");
+
+const TELEMETRY_AUDIT_ACTIVATED = "devtools.accessibility.audit_activated";
+const FILTER_LABELS = {
+  [FILTERS.NONE]: "accessibility.filter.none",
+  [FILTERS.ALL]: "accessibility.filter.all2",
+  [FILTERS.CONTRAST]: "accessibility.filter.contrast",
+  [FILTERS.KEYBOARD]: "accessibility.filter.keyboard",
+  [FILTERS.TEXT_LABEL]: "accessibility.filter.textLabel",
+};
+
+class AccessibilityTreeFilter extends Component {
+  static get propTypes() {
+    return {
+      auditing: PropTypes.array.isRequired,
+      filters: PropTypes.object.isRequired,
+      dispatch: PropTypes.func.isRequired,
+      describedby: PropTypes.string,
+      toolboxDoc: PropTypes.object.isRequired,
+      audit: PropTypes.func.isRequired,
+    };
+  }
+
+  async toggleFilter(filterKey) {
+    const { audit: auditFunc, dispatch, filters } = this.props;
+
+    if (filterKey !== FILTERS.NONE && !filters[filterKey]) {
+      if (gTelemetry) {
+        gTelemetry.keyedScalarAdd(TELEMETRY_AUDIT_ACTIVATED, filterKey, 1);
+      }
+
+      dispatch(actions.auditing(filterKey));
+      await dispatch(actions.audit(auditFunc, filterKey));
+    }
+
+    // We wait to dispatch filter toggle until the tree is ready to be filtered
+    // right after the audit. This is to make sure that we render an empty tree
+    // (filtered) while the audit is running.
+    dispatch(actions.filterToggle(filterKey));
+  }
+
+  onClick(filterKey) {
+    this.toggleFilter(filterKey);
+  }
+
+  render() {
+    const { auditing, filters, describedby, toolboxDoc } = this.props;
+    const toolbarLabelID = "accessibility-tree-filters-label";
+    const filterNoneChecked = !Object.values(filters).includes(true);
+    const items = [
+      MenuItem({
+        key: FILTERS.NONE,
+        checked: filterNoneChecked,
+        className: `filter ${FILTERS.NONE}`,
+        label: L10N.getStr(FILTER_LABELS[FILTERS.NONE]),
+        onClick: this.onClick.bind(this, FILTERS.NONE),
+        disabled: !!auditing.length,
+      }),
+      hr({ key: "hr-1" }),
+    ];
+
+    const { [FILTERS.ALL]: filterAllChecked, ...filtersWithoutAll } = filters;
+    items.push(
+      MenuItem({
+        key: FILTERS.ALL,
+        checked: filterAllChecked,
+        className: `filter ${FILTERS.ALL}`,
+        label: L10N.getStr(FILTER_LABELS[FILTERS.ALL]),
+        onClick: this.onClick.bind(this, FILTERS.ALL),
+        disabled: !!auditing.length,
+      }),
+      hr({ key: "hr-2" }),
+      Object.entries(filtersWithoutAll).map(([filterKey, active]) =>
+        MenuItem({
+          key: filterKey,
+          checked: active,
+          className: `filter ${filterKey}`,
+          label: L10N.getStr(FILTER_LABELS[filterKey]),
+          onClick: this.onClick.bind(this, filterKey),
+          disabled: !!auditing.length,
+        })
+      )
+    );
+
+    let label;
+    if (filterNoneChecked) {
+      label = L10N.getStr(FILTER_LABELS[FILTERS.NONE]);
+    } else if (filterAllChecked) {
+      label = L10N.getStr(FILTER_LABELS[FILTERS.ALL]);
+    } else {
+      label = Object.keys(filtersWithoutAll)
+        .filter(filterKey => filtersWithoutAll[filterKey])
+        .map(filterKey => L10N.getStr(FILTER_LABELS[filterKey]))
+        .join(", ");
+    }
+
+    return div(
+      {
+        role: "group",
+        className: "accessibility-tree-filters",
+        "aria-labelledby": toolbarLabelID,
+        "aria-describedby": describedby,
+      },
+      span(
+        { id: toolbarLabelID, role: "presentation" },
+        L10N.getStr("accessibility.tree.filters")
+      ),
+      MenuButton(
+        {
+          menuId: "accessibility-tree-filters-menu",
+          toolboxDoc,
+          className: `devtools-button badge toolbar-menu-button filters`,
+          label,
+        },
+        MenuList({}, items)
+      )
+    );
+  }
+}
+
+const mapStateToProps = ({ audit: { filters, auditing } }) => {
+  return { filters, auditing };
+};
+
+// Exports from this module
+module.exports = connect(mapStateToProps)(AccessibilityTreeFilter);
diff --git a/devtools/client/accessibility/components/Accessible.js b/devtools/client/accessibility/components/Accessible.js
new file mode 100644
index 0000000000..02467ccaab
--- /dev/null
+++ b/devtools/client/accessibility/components/Accessible.js
@@ -0,0 +1,563 @@
+/* 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/. */
+"use strict";
+
+/* global EVENTS, gTelemetry */
+
+// React & Redux
+const {
+  createFactory,
+  Component,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const {
+  div,
+  span,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  findDOMNode,
+} = require("resource://devtools/client/shared/vendor/react-dom.js");
+const {
+  connect,
+} = require("resource://devtools/client/shared/vendor/react-redux.js");
+
+const {
+  TREE_ROW_HEIGHT,
+  ORDERED_PROPS,
+  ACCESSIBLE_EVENTS,
+  VALUE_FLASHING_DURATION,
+} = require("resource://devtools/client/accessibility/constants.js");
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+const {
+  flashElementOn,
+  flashElementOff,
+} = require("resource://devtools/client/inspector/markup/utils.js");
+const {
+  updateDetails,
+} = require("resource://devtools/client/accessibility/actions/details.js");
+const {
+  select,
+  unhighlight,
+} = require("resource://devtools/client/accessibility/actions/accessibles.js");
+
+const VirtualizedTree = createFactory(
+  require("resource://devtools/client/shared/components/VirtualizedTree.js")
+);
+// Reps
+const {
+  REPS,
+  MODE,
+} = require("resource://devtools/client/shared/components/reps/index.js");
+const { Rep, ElementNode, Accessible: AccessibleRep, Obj } = REPS;
+
+const {
+  translateNodeFrontToGrip,
+} = require("resource://devtools/client/inspector/shared/utils.js");
+
+loader.lazyRequireGetter(
+  this,
+  "openContentLink",
+  "resource://devtools/client/shared/link.js",
+  true
+);
+
+const TELEMETRY_NODE_INSPECTED_COUNT =
+  "devtools.accessibility.node_inspected_count";
+
+const TREE_DEPTH_PADDING_INCREMENT = 20;
+
+class AccessiblePropertyClass extends Component {
+  static get propTypes() {
+    return {
+      accessibleFrontActorID: PropTypes.string,
+      object: PropTypes.any,
+      focused: PropTypes.bool,
+      children: PropTypes.func,
+    };
+  }
+
+  componentDidUpdate({
+    object: prevObject,
+    accessibleFrontActorID: prevAccessibleFrontActorID,
+  }) {
+    const { accessibleFrontActorID, object, focused } = this.props;
+    // Fast check if row is focused or if the value did not update.
+    if (
+      focused ||
+      accessibleFrontActorID !== prevAccessibleFrontActorID ||
+      prevObject === object ||
+      (object && prevObject && typeof object === "object")
+    ) {
+      return;
+    }
+
+    this.flashRow();
+  }
+
+  flashRow() {
+    const row = findDOMNode(this);
+    flashElementOn(row);
+    if (this._flashMutationTimer) {
+      clearTimeout(this._flashMutationTimer);
+      this._flashMutationTimer = null;
+    }
+    this._flashMutationTimer = setTimeout(() => {
+      flashElementOff(row);
+    }, VALUE_FLASHING_DURATION);
+  }
+
+  render() {
+    return this.props.children();
+  }
+}
+
+const AccessibleProperty = createFactory(AccessiblePropertyClass);
+
+class Accessible extends Component {
+  static get propTypes() {
+    return {
+      accessibleFront: PropTypes.object,
+      dispatch: PropTypes.func.isRequired,
+      nodeFront: PropTypes.object,
+      items: PropTypes.array,
+      labelledby: PropTypes.string.isRequired,
+      parents: PropTypes.object,
+      relations: PropTypes.object,
+      toolbox: PropTypes.object.isRequired,
+      toolboxHighlighter: PropTypes.object.isRequired,
+      highlightAccessible: PropTypes.func.isRequired,
+      unhighlightAccessible: PropTypes.func.isRequired,
+    };
+  }
+
+  constructor(props) {
+    super(props);
+
+    this.state = {
+      expanded: new Set(),
+      active: null,
+      focused: null,
+    };
+
+    this.onAccessibleInspected = this.onAccessibleInspected.bind(this);
+    this.renderItem = this.renderItem.bind(this);
+    this.update = this.update.bind(this);
+  }
+
+  // FIXME: https://bugzilla.mozilla.org/show_bug.cgi?id=1774507
+  UNSAFE_componentWillMount() {
+    window.on(
+      EVENTS.NEW_ACCESSIBLE_FRONT_INSPECTED,
+      this.onAccessibleInspected
+    );
+  }
+
+  // FIXME: https://bugzilla.mozilla.org/show_bug.cgi?id=1774507
+  UNSAFE_componentWillReceiveProps({ accessibleFront }) {
+    const oldAccessibleFront = this.props.accessibleFront;
+
+    if (oldAccessibleFront) {
+      if (
+        accessibleFront &&
+        accessibleFront.actorID === oldAccessibleFront.actorID
+      ) {
+        return;
+      }
+      ACCESSIBLE_EVENTS.forEach(event =>
+        oldAccessibleFront.off(event, this.update)
+      );
+    }
+
+    if (accessibleFront) {
+      ACCESSIBLE_EVENTS.forEach(event =>
+        accessibleFront.on(event, this.update)
+      );
+    }
+  }
+
+  componentDidUpdate(prevProps) {
+    if (
+      this.props.accessibleFront &&
+      !this.props.accessibleFront.isDestroyed() &&
+      this.props.accessibleFront !== prevProps.accessibleFront
+    ) {
+      window.emit(EVENTS.PROPERTIES_UPDATED);
+    }
+  }
+
+  componentWillUnmount() {
+    window.off(
+      EVENTS.NEW_ACCESSIBLE_FRONT_INSPECTED,
+      this.onAccessibleInspected
+    );
+
+    const { accessibleFront } = this.props;
+    if (accessibleFront) {
+      ACCESSIBLE_EVENTS.forEach(event =>
+        accessibleFront.off(event, this.update)
+      );
+    }
+  }
+
+  onAccessibleInspected() {
+    const { props } = this.refs;
+    if (props) {
+      props.refs.tree.focus();
+    }
+  }
+
+  update() {
+    const { dispatch, accessibleFront } = this.props;
+    if (accessibleFront.isDestroyed()) {
+      return;
+    }
+
+    dispatch(updateDetails(accessibleFront));
+  }
+
+  setExpanded(item, isExpanded) {
+    const { expanded } = this.state;
+
+    if (isExpanded) {
+      expanded.add(item.path);
+    } else {
+      expanded.delete(item.path);
+    }
+
+    this.setState({ expanded });
+  }
+
+  async showHighlighter(nodeFront) {
+    if (!this.props.toolboxHighlighter) {
+      return;
+    }
+
+    await this.props.toolboxHighlighter.highlight(nodeFront);
+  }
+
+  async hideHighlighter() {
+    if (!this.props.toolboxHighlighter) {
+      return;
+    }
+
+    await this.props.toolboxHighlighter.unhighlight();
+  }
+
+  showAccessibleHighlighter(accessibleFront) {
+    this.props.dispatch(unhighlight());
+    this.props.highlightAccessible(accessibleFront);
+  }
+
+  hideAccessibleHighlighter(accessibleFront) {
+    this.props.dispatch(unhighlight());
+    this.props.unhighlightAccessible(accessibleFront);
+  }
+
+  async selectNode(nodeFront, reason = "accessibility") {
+    if (gTelemetry) {
+      gTelemetry.scalarAdd(TELEMETRY_NODE_INSPECTED_COUNT, 1);
+    }
+
+    if (!this.props.toolbox) {
+      return;
+    }
+
+    const inspector = await this.props.toolbox.selectTool("inspector");
+    inspector.selection.setNodeFront(nodeFront, reason);
+  }
+
+  async selectAccessible(accessibleFront) {
+    if (!accessibleFront) {
+      return;
+    }
+
+    await this.props.dispatch(select(accessibleFront));
+
+    const { props } = this.refs;
+    if (props) {
+      props.refs.tree.blur();
+    }
+    await this.setState({ active: null, focused: null });
+
+    window.emit(EVENTS.NEW_ACCESSIBLE_FRONT_INSPECTED);
+  }
+
+  openLink(link, e) {
+    openContentLink(link);
+  }
+
+  renderItem(item, depth, focused, arrow, expanded) {
+    const object = item.contents;
+    const valueProps = {
+      object,
+      mode: MODE.TINY,
+      title: "Object",
+      openLink: this.openLink,
+    };
+
+    if (isNodeFront(object)) {
+      valueProps.defaultRep = ElementNode;
+      valueProps.onDOMNodeMouseOut = () => this.hideHighlighter();
+      valueProps.onDOMNodeMouseOver = () =>
+        this.showHighlighter(this.props.nodeFront);
+
+      valueProps.inspectIconTitle = L10N.getStr(
+        "accessibility.accessible.selectNodeInInspector.title"
+      );
+      valueProps.onInspectIconClick = () =>
+        this.selectNode(this.props.nodeFront);
+    } else if (isAccessibleFront(object)) {
+      const target = findAccessibleTarget(this.props.relations, object.actor);
+      valueProps.defaultRep = AccessibleRep;
+      valueProps.onAccessibleMouseOut = () =>
+        this.hideAccessibleHighlighter(target);
+      valueProps.onAccessibleMouseOver = () =>
+        this.showAccessibleHighlighter(target);
+      valueProps.inspectIconTitle = L10N.getStr(
+        "accessibility.accessible.selectElement.title"
+      );
+      valueProps.onInspectIconClick = (obj, e) => {
+        e.stopPropagation();
+        this.selectAccessible(target);
+      };
+      valueProps.separatorText = "";
+    } else if (item.name === "relations") {
+      valueProps.defaultRep = Obj;
+    } else {
+      valueProps.noGrip = true;
+    }
+
+    const classList = ["node", "object-node"];
+    if (focused) {
+      classList.push("focused");
+    }
+
+    const depthPadding = depth * TREE_DEPTH_PADDING_INCREMENT;
+
+    return AccessibleProperty(
+      {
+        object,
+        focused,
+        accessibleFrontActorID: this.props.accessibleFront.actorID,
+      },
+      () =>
+        div(
+          {
+            className: classList.join(" "),
+            style: {
+              paddingInlineStart: depthPadding,
+              inlineSize: `calc(var(--accessibility-properties-item-width) - ${depthPadding}px)`,
+            },
+            onClick: e => {
+              if (e.target.classList.contains("theme-twisty")) {
+                this.setExpanded(item, !expanded);
+              }
+            },
+          },
+          arrow,
+          span({ className: "object-label" }, item.name),
+          span({ className: "object-delimiter" }, ":"),
+          span({ className: "object-value" }, Rep(valueProps) || "")
+        )
+    );
+  }
+
+  render() {
+    const { expanded, active, focused } = this.state;
+    const { items, parents, accessibleFront, labelledby } = this.props;
+
+    if (accessibleFront) {
+      return VirtualizedTree({
+        ref: "props",
+        key: "accessible-properties",
+        itemHeight: TREE_ROW_HEIGHT,
+        getRoots: () => items,
+        getKey: item => item.path,
+        getParent: item => parents.get(item),
+        getChildren: item => item.children,
+        isExpanded: item => expanded.has(item.path),
+        onExpand: item => this.setExpanded(item, true),
+        onCollapse: item => this.setExpanded(item, false),
+        onFocus: item => {
+          if (this.state.focused !== item.path) {
+            this.setState({ focused: item.path });
+          }
+        },
+        onActivate: item => {
+          if (item == null) {
+            this.setState({ active: null });
+          } else if (this.state.active !== item.path) {
+            this.setState({ active: item.path });
+          }
+        },
+        focused: findByPath(focused, items),
+        active: findByPath(active, items),
+        renderItem: this.renderItem,
+        labelledby,
+      });
+    }
+
+    return div(
+      { className: "info" },
+      L10N.getStr("accessibility.accessible.notAvailable")
+    );
+  }
+}
+
+/**
+ * Match accessibility object from relations targets to the grip that's being activated.
+ * @param  {Object} relations  Object containing relations grouped by type and targets.
+ * @param  {String} actorID    Actor ID to match to the relation target.
+ * @return {Object}            Accessible front that matches the relation target.
+ */
+const findAccessibleTarget = (relations, actorID) => {
+  for (const relationType in relations) {
+    let targets = relations[relationType];
+    targets = Array.isArray(targets) ? targets : [targets];
+    for (const target of targets) {
+      if (target.actorID === actorID) {
+        return target;
+      }
+    }
+  }
+
+  return null;
+};
+
+/**
+ * Find an item based on a given path.
+ * @param  {String} path
+ *         Key of the item to be looked up.
+ * @param  {Array}  items
+ *         Accessibility properties array.
+ * @return {Object?}
+ *         Possibly found item.
+ */
+const findByPath = (path, items) => {
+  for (const item of items) {
+    if (item.path === path) {
+      return item;
+    }
+
+    const found = findByPath(path, item.children);
+    if (found) {
+      return found;
+    }
+  }
+  return null;
+};
+
+/**
+ * Check if a given property is a DOMNode front.
+ * @param  {Object?} value A property to check for being a DOMNode.
+ * @return {Boolean}       A flag that indicates whether a property is a DOMNode.
+ */
+const isNodeFront = value => value && value.typeName === "domnode";
+
+/**
+ * Check if a given property is an Accessible front.
+ * @param  {Object?} value A property to check for being an Accessible.
+ * @return {Boolean}       A flag that indicates whether a property is an Accessible.
+ */
+const isAccessibleFront = value => value && value.typeName === "accessible";
+
+/**
+ * While waiting for a reps fix in https://github.com/firefox-devtools/reps/issues/92,
+ * translate accessibleFront to a grip-like object that can be used with an Accessible
+ * rep.
+ *
+ * @params  {accessibleFront} accessibleFront
+ *          The AccessibleFront for which we want to create a grip-like object.
+ * @returns {Object} a grip-like object that can be used with Reps.
+ */
+const translateAccessibleFrontToGrip = accessibleFront => ({
+  actor: accessibleFront.actorID,
+  typeName: accessibleFront.typeName,
+  preview: {
+    name: accessibleFront.name,
+    role: accessibleFront.role,
+    // All the grid containers are assumed to be in the Accessibility tree.
+    isConnected: true,
+  },
+});
+
+const translateNodeFrontToGripWrapper = nodeFront => ({
+  ...translateNodeFrontToGrip(nodeFront),
+  typeName: nodeFront.typeName,
+});
+
+/**
+ * Build props ingestible by VirtualizedTree component.
+ * @param  {Object} props      Component properties to be processed.
+ * @param  {String} parentPath Unique path that is used to identify a Tree Node.
+ * @return {Object}            Processed properties.
+ */
+const makeItemsForDetails = (props, parentPath) =>
+  Object.getOwnPropertyNames(props).map(name => {
+    let children = [];
+    const path = `${parentPath}/${name}`;
+    let contents = props[name];
+
+    if (contents) {
+      if (isNodeFront(contents)) {
+        contents = translateNodeFrontToGripWrapper(contents);
+        name = "DOMNode";
+      } else if (isAccessibleFront(contents)) {
+        contents = translateAccessibleFrontToGrip(contents);
+      } else if (Array.isArray(contents) || typeof contents === "object") {
+        children = makeItemsForDetails(contents, path);
+      }
+    }
+
+    return { name, path, contents, children };
+  });
+
+const makeParentMap = items => {
+  const map = new WeakMap();
+
+  function _traverse(item) {
+    if (item.children.length) {
+      for (const child of item.children) {
+        map.set(child, item);
+        _traverse(child);
+      }
+    }
+  }
+
+  items.forEach(_traverse);
+  return map;
+};
+
+const mapStateToProps = ({ details }) => {
+  const {
+    accessible: accessibleFront,
+    DOMNode: nodeFront,
+    relations,
+  } = details;
+  if (!accessibleFront || !nodeFront) {
+    return {};
+  }
+
+  const items = makeItemsForDetails(
+    ORDERED_PROPS.reduce((props, key) => {
+      if (key === "DOMNode") {
+        props.nodeFront = nodeFront;
+      } else if (key === "relations") {
+        props.relations = relations;
+      } else {
+        props[key] = accessibleFront[key];
+      }
+
+      return props;
+    }, {}),
+    ""
+  );
+  const parents = makeParentMap(items);
+
+  return { accessibleFront, nodeFront, items, parents, relations };
+};
+
+module.exports = connect(mapStateToProps)(Accessible);
diff --git a/devtools/client/accessibility/components/AuditController.js b/devtools/client/accessibility/components/AuditController.js
new file mode 100644
index 0000000000..e6ada9a0a9
--- /dev/null
+++ b/devtools/client/accessibility/components/AuditController.js
@@ -0,0 +1,90 @@
+/* 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/. */
+
+"use strict";
+
+const React = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+
+class AuditController extends React.Component {
+  static get propTypes() {
+    return {
+      accessibleFront: PropTypes.object.isRequired,
+      children: PropTypes.any,
+    };
+  }
+
+  constructor(props) {
+    super(props);
+
+    const {
+      accessibleFront: { checks },
+    } = props;
+    this.state = {
+      checks,
+    };
+
+    this.onAudited = this.onAudited.bind(this);
+  }
+
+  // FIXME: https://bugzilla.mozilla.org/show_bug.cgi?id=1774507
+  UNSAFE_componentWillMount() {
+    const { accessibleFront } = this.props;
+    accessibleFront.on("audited", this.onAudited);
+  }
+
+  componentDidMount() {
+    this.maybeRequestAudit();
+  }
+
+  componentDidUpdate() {
+    this.maybeRequestAudit();
+  }
+
+  componentWillUnmount() {
+    const { accessibleFront } = this.props;
+    accessibleFront.off("audited", this.onAudited);
+  }
+
+  onAudited() {
+    const { accessibleFront } = this.props;
+    if (accessibleFront.isDestroyed()) {
+      // Accessible front is being removed, stop listening for 'audited' events.
+      accessibleFront.off("audited", this.onAudited);
+      return;
+    }
+
+    this.setState({ checks: accessibleFront.checks });
+  }
+
+  maybeRequestAudit() {
+    const { accessibleFront } = this.props;
+    if (accessibleFront.isDestroyed()) {
+      // Accessible front is being removed, stop listening for 'audited' events.
+      accessibleFront.off("audited", this.onAudited);
+      return;
+    }
+
+    if (accessibleFront.checks) {
+      return;
+    }
+
+    accessibleFront.audit().catch(error => {
+      // If the actor was destroyed (due to a connection closed for instance) do
+      // nothing, otherwise log a warning
+      if (!accessibleFront.isDestroyed()) {
+        console.warn(error);
+      }
+    });
+  }
+
+  render() {
+    const { children } = this.props;
+    const { checks } = this.state;
+
+    return React.Children.only(React.cloneElement(children, { checks }));
+  }
+}
+
+module.exports = AuditController;
diff --git a/devtools/client/accessibility/components/AuditFilter.js b/devtools/client/accessibility/components/AuditFilter.js
new file mode 100644
index 0000000000..361a1c30a7
--- /dev/null
+++ b/devtools/client/accessibility/components/AuditFilter.js
@@ -0,0 +1,91 @@
+/* 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/. */
+
+"use strict";
+
+const React = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  connect,
+} = require("resource://devtools/client/shared/vendor/react-redux.js");
+
+const {
+  isFiltered,
+} = require("resource://devtools/client/accessibility/utils/audit.js");
+const {
+  FILTERS,
+} = require("resource://devtools/client/accessibility/constants.js");
+const {
+  accessibility: {
+    AUDIT_TYPE,
+    SCORES: { BEST_PRACTICES, FAIL, WARNING },
+  },
+} = require("resource://devtools/shared/constants.js");
+
+function validateCheck({ error, score }) {
+  return !error && [BEST_PRACTICES, FAIL, WARNING].includes(score);
+}
+
+const AUDIT_TYPE_TO_FILTER = {
+  [AUDIT_TYPE.CONTRAST]: {
+    filterKey: FILTERS.CONTRAST,
+    validator: validateCheck,
+  },
+  [AUDIT_TYPE.KEYBOARD]: {
+    filterKey: FILTERS.KEYBOARD,
+    validator: validateCheck,
+  },
+  [AUDIT_TYPE.TEXT_LABEL]: {
+    filterKey: FILTERS.TEXT_LABEL,
+    validator: validateCheck,
+  },
+};
+
+class AuditFilter extends React.Component {
+  static get propTypes() {
+    return {
+      checks: PropTypes.object,
+      children: PropTypes.any,
+      filters: PropTypes.object.isRequired,
+    };
+  }
+
+  isVisible(filters) {
+    return !isFiltered(filters);
+  }
+
+  shouldHide() {
+    const { filters, checks } = this.props;
+    if (this.isVisible(filters)) {
+      return false;
+    }
+
+    if (!checks || Object.values(checks).every(check => check == null)) {
+      return true;
+    }
+
+    for (const type in checks) {
+      if (
+        AUDIT_TYPE_TO_FILTER[type] &&
+        checks[type] &&
+        filters[AUDIT_TYPE_TO_FILTER[type].filterKey] &&
+        AUDIT_TYPE_TO_FILTER[type].validator(checks[type])
+      ) {
+        return false;
+      }
+    }
+
+    return true;
+  }
+
+  render() {
+    return this.shouldHide() ? null : this.props.children;
+  }
+}
+
+const mapStateToProps = ({ audit: { filters } }) => {
+  return { filters };
+};
+
+module.exports = connect(mapStateToProps)(AuditFilter);
diff --git a/devtools/client/accessibility/components/AuditProgressOverlay.js b/devtools/client/accessibility/components/AuditProgressOverlay.js
new file mode 100644
index 0000000000..3c16998bcf
--- /dev/null
+++ b/devtools/client/accessibility/components/AuditProgressOverlay.js
@@ -0,0 +1,92 @@
+/* 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/. */
+
+"use strict";
+
+const React = require("resource://devtools/client/shared/vendor/react.js");
+const ReactDOM = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  connect,
+} = require("resource://devtools/client/shared/vendor/react-redux.js");
+
+const FluentReact = require("resource://devtools/client/shared/vendor/fluent-react.js");
+const Localized = React.createFactory(FluentReact.Localized);
+
+/**
+ * Helper functional component to render an accessible text progressbar.
+ * @param {Object} props
+ *        - id for the progressbar element
+ *        - fluentId: localized string id
+ */
+function TextProgressBar({ id, fluentId }) {
+  return Localized(
+    {
+      id: fluentId,
+      attrs: { "aria-valuetext": true },
+    },
+    ReactDOM.span({
+      id,
+      key: id,
+      role: "progressbar",
+    })
+  );
+}
+
+class AuditProgressOverlay extends React.Component {
+  static get propTypes() {
+    return {
+      auditing: PropTypes.array.isRequired,
+      total: PropTypes.number,
+      percentage: PropTypes.number,
+    };
+  }
+
+  render() {
+    const { auditing, percentage, total } = this.props;
+    if (auditing.length === 0) {
+      return null;
+    }
+
+    const id = "audit-progress-container";
+
+    if (total == null) {
+      return TextProgressBar({
+        id,
+        fluentId: "accessibility-progress-initializing",
+      });
+    }
+
+    if (percentage === 100) {
+      return TextProgressBar({
+        id,
+        fluentId: "accessibility-progress-finishing",
+      });
+    }
+
+    return ReactDOM.span(
+      {
+        id,
+        key: id,
+      },
+      Localized({
+        id: "accessibility-progress-progressbar",
+        $nodeCount: total,
+      }),
+      ReactDOM.progress({
+        max: 100,
+        value: percentage,
+        className: "audit-progress-progressbar",
+        "aria-labelledby": id,
+      })
+    );
+  }
+}
+
+const mapStateToProps = ({ audit: { auditing, progress } }) => {
+  const { total, percentage } = progress || {};
+  return { auditing, total, percentage };
+};
+
+module.exports = connect(mapStateToProps)(AuditProgressOverlay);
diff --git a/devtools/client/accessibility/components/Badge.js b/devtools/client/accessibility/components/Badge.js
new file mode 100644
index 0000000000..207bb96f55
--- /dev/null
+++ b/devtools/client/accessibility/components/Badge.js
@@ -0,0 +1,40 @@
+/* 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/. */
+"use strict";
+
+// React
+const {
+  Component,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const {
+  span,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+
+class Badge extends Component {
+  static get propTypes() {
+    return {
+      score: PropTypes.string.isRequired,
+      label: PropTypes.string.isRequired,
+      ariaLabel: PropTypes.string,
+      tooltip: PropTypes.string,
+    };
+  }
+
+  render() {
+    const { score, label, ariaLabel, tooltip } = this.props;
+
+    return span(
+      {
+        className: `audit-badge badge`,
+        "data-score": score,
+        title: tooltip,
+        "aria-label": ariaLabel || label,
+      },
+      label
+    );
+  }
+}
+
+module.exports = Badge;
diff --git a/devtools/client/accessibility/components/Badges.js b/devtools/client/accessibility/components/Badges.js
new file mode 100644
index 0000000000..00079d21b6
--- /dev/null
+++ b/devtools/client/accessibility/components/Badges.js
@@ -0,0 +1,88 @@
+/* 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/. */
+"use strict";
+
+// React
+const {
+  Component,
+  createFactory,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  span,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+
+const {
+  accessibility: { AUDIT_TYPE },
+} = require("resource://devtools/shared/constants.js");
+
+loader.lazyGetter(this, "ContrastBadge", () =>
+  createFactory(
+    require("resource://devtools/client/accessibility/components/ContrastBadge.js")
+  )
+);
+
+loader.lazyGetter(this, "KeyboardBadge", () =>
+  createFactory(
+    require("resource://devtools/client/accessibility/components/KeyboardBadge.js")
+  )
+);
+
+loader.lazyGetter(this, "TextLabelBadge", () =>
+  createFactory(
+    require("resource://devtools/client/accessibility/components/TextLabelBadge.js")
+  )
+);
+
+function getComponentForAuditType(type) {
+  const auditTypeToComponentMap = {
+    [AUDIT_TYPE.CONTRAST]: ContrastBadge,
+    [AUDIT_TYPE.KEYBOARD]: KeyboardBadge,
+    [AUDIT_TYPE.TEXT_LABEL]: TextLabelBadge,
+  };
+
+  return auditTypeToComponentMap[type];
+}
+
+class Badges extends Component {
+  static get propTypes() {
+    return {
+      checks: PropTypes.object,
+    };
+  }
+
+  render() {
+    const { checks } = this.props;
+    if (!checks) {
+      return null;
+    }
+
+    const items = [];
+    for (const type in checks) {
+      const component = getComponentForAuditType(type);
+      if (checks[type] && component) {
+        items.push(component({ key: type, ...checks[type] }));
+      }
+    }
+
+    if (items.length === 0) {
+      return null;
+    }
+
+    return span(
+      {
+        className: "badges",
+        role: "group",
+        "aria-label": L10N.getStr("accessibility.badges"),
+      },
+      items
+    );
+  }
+}
+
+module.exports = Badges;
diff --git a/devtools/client/accessibility/components/Button.js b/devtools/client/accessibility/components/Button.js
new file mode 100644
index 0000000000..92cd90a56c
--- /dev/null
+++ b/devtools/client/accessibility/components/Button.js
@@ -0,0 +1,112 @@
+/* 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/. */
+
+"use strict";
+
+const {
+  Component,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  button,
+  span,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+
+const defaultProps = {
+  disabled: false,
+  busy: false,
+  title: null,
+  children: null,
+  className: "",
+};
+
+/**
+ * Button component that handles keyboard in an accessible way. When user
+ * uses the mouse to hover/click on the button, there is no focus
+ * highlighting. However if the user uses a keyboard to focus on the button,
+ * it will have focus highlighting in the form of an outline.
+ */
+class Button extends Component {
+  static get propTypes() {
+    return {
+      disabled: PropTypes.bool,
+      busy: PropTypes.bool,
+      title: PropTypes.string,
+      children: PropTypes.string,
+      className: PropTypes.string,
+    };
+  }
+
+  static get defaultProps() {
+    return defaultProps;
+  }
+
+  render() {
+    const className = [
+      ...this.props.className.split(" "),
+      "devtools-button",
+    ].join(" ");
+    const props = Object.assign({}, this.props, {
+      className,
+      "aria-busy": this.props.busy.toString(),
+      busy: this.props.busy.toString(),
+    });
+
+    const classList = ["btn-content"];
+    if (this.props.busy) {
+      classList.push("devtools-throbber");
+    }
+
+    return button(
+      props,
+      span(
+        {
+          className: classList.join(" "),
+          tabIndex: -1,
+        },
+        this.props.children
+      )
+    );
+  }
+}
+
+function ToggleButton(props) {
+  const {
+    active,
+    busy,
+    disabled,
+    label,
+    className,
+    onClick,
+    onKeyDown,
+    tooltip,
+  } = props;
+  const classList = [...className.split(" "), "toggle-button"];
+
+  if (active) {
+    classList.push("checked");
+  }
+
+  if (busy) {
+    classList.push("devtools-throbber");
+  }
+
+  return button(
+    {
+      disabled,
+      "aria-pressed": active === true,
+      "aria-busy": busy,
+      className: classList.join(" "),
+      onClick,
+      onKeyDown,
+      title: tooltip,
+    },
+    label
+  );
+}
+
+module.exports = {
+  Button,
+  ToggleButton,
+};
diff --git a/devtools/client/accessibility/components/Check.js b/devtools/client/accessibility/components/Check.js
new file mode 100644
index 0000000000..3ca6c9c39a
--- /dev/null
+++ b/devtools/client/accessibility/components/Check.js
@@ -0,0 +1,157 @@
+/* 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/. */
+"use strict";
+
+// React
+const {
+  Component,
+  createFactory,
+  PureComponent,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const ReactDOM = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+
+const FluentReact = require("resource://devtools/client/shared/vendor/fluent-react.js");
+const Localized = createFactory(FluentReact.Localized);
+
+const { openDocLink } = require("resource://devtools/client/shared/link.js");
+
+const {
+  accessibility: {
+    SCORES: { BEST_PRACTICES, FAIL, WARNING },
+  },
+} = require("resource://devtools/shared/constants.js");
+
+/**
+ * A map of accessibility scores to the text descriptions of check icons.
+ */
+const SCORE_TO_ICON_MAP = {
+  [BEST_PRACTICES]: {
+    l10nId: "accessibility-best-practices",
+    src: "chrome://devtools/skin/images/info.svg",
+  },
+  [FAIL]: {
+    l10nId: "accessibility-fail",
+    src: "chrome://devtools/skin/images/error.svg",
+  },
+  [WARNING]: {
+    l10nId: "accessibility-warning",
+    src: "chrome://devtools/skin/images/alert.svg",
+  },
+};
+
+/**
+ * Localized "Learn more" link that opens a new tab with relevant documentation.
+ */
+class LearnMoreClass extends PureComponent {
+  static get propTypes() {
+    return {
+      href: PropTypes.string,
+      l10nId: PropTypes.string.isRequired,
+      onClick: PropTypes.func,
+    };
+  }
+
+  static get defaultProps() {
+    return {
+      href: "#",
+      l10nId: null,
+      onClick: LearnMoreClass.openDocOnClick,
+    };
+  }
+
+  static openDocOnClick(event) {
+    event.preventDefault();
+    openDocLink(event.target.href);
+  }
+
+  render() {
+    const { href, l10nId, onClick } = this.props;
+    const className = "link";
+
+    return Localized({ id: l10nId }, ReactDOM.a({ className, href, onClick }));
+  }
+}
+
+const LearnMore = createFactory(LearnMoreClass);
+
+/**
+ * Renders icon with text description for the accessibility check.
+ *
+ * @param {Object}
+ *        Options:
+ *          - score: value from SCORES from "devtools/shared/constants"
+ */
+function Icon({ score }) {
+  const { l10nId, src } = SCORE_TO_ICON_MAP[score];
+
+  return Localized(
+    { id: l10nId, attrs: { alt: true } },
+    ReactDOM.img({ src, "data-score": score, className: "icon" })
+  );
+}
+
+/**
+ * Renders text description of the accessibility check.
+ *
+ * @param {Object}
+ *        Options:
+ *          - args:   arguments for fluent localized string
+ *          - href:   url for the learn more link pointing to MDN
+ *          - l10nId: fluent localization id
+ */
+function Annotation({ args, href, l10nId }) {
+  return Localized(
+    {
+      id: l10nId,
+      a: LearnMore({ l10nId: "accessibility-learn-more", href }),
+      ...args,
+    },
+    ReactDOM.p({ className: "accessibility-check-annotation" })
+  );
+}
+
+/**
+ * Component for rendering a check for accessibliity checks section,
+ * warnings and best practices suggestions association with a given
+ * accessibility object in the accessibility tree.
+ */
+class Check extends Component {
+  static get propTypes() {
+    return {
+      getAnnotation: PropTypes.func.isRequired,
+      id: PropTypes.string.isRequired,
+      issue: PropTypes.string.isRequired,
+      score: PropTypes.string.isRequired,
+    };
+  }
+
+  render() {
+    const { getAnnotation, id, issue, score } = this.props;
+
+    return ReactDOM.div(
+      {
+        role: "presentation",
+        tabIndex: "-1",
+        className: "accessibility-check",
+      },
+      Localized(
+        {
+          id,
+        },
+        ReactDOM.h3({ className: "accessibility-check-header" })
+      ),
+      ReactDOM.div(
+        {
+          role: "presentation",
+          tabIndex: "-1",
+        },
+        Icon({ score }),
+        Annotation({ ...getAnnotation(issue) })
+      )
+    );
+  }
+}
+
+module.exports = Check;
diff --git a/devtools/client/accessibility/components/Checks.js b/devtools/client/accessibility/components/Checks.js
new file mode 100644
index 0000000000..f2b4e4835a
--- /dev/null
+++ b/devtools/client/accessibility/components/Checks.js
@@ -0,0 +1,117 @@
+/* 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/. */
+"use strict";
+
+// React
+const {
+  Component,
+  createFactory,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const {
+  connect,
+} = require("resource://devtools/client/shared/vendor/react-redux.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  div,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+
+const List = createFactory(
+  require("resource://devtools/client/shared/components/List.js").List
+);
+const ColorContrastCheck = createFactory(
+  require("resource://devtools/client/accessibility/components/ColorContrastAccessibility.js")
+    .ColorContrastCheck
+);
+const TextLabelCheck = createFactory(
+  require("resource://devtools/client/accessibility/components/TextLabelCheck.js")
+);
+const KeyboardCheck = createFactory(
+  require("resource://devtools/client/accessibility/components/KeyboardCheck.js")
+);
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+
+const {
+  accessibility: { AUDIT_TYPE },
+} = require("resource://devtools/shared/constants.js");
+
+function EmptyChecks() {
+  return div(
+    {
+      className: "checks-empty",
+      role: "presentation",
+      tabIndex: "-1",
+    },
+    L10N.getStr("accessibility.checks.empty2")
+  );
+}
+
+// Component that is responsible for rendering accessible audit data in the a11y panel
+// sidebar.
+class Checks extends Component {
+  static get propTypes() {
+    return {
+      audit: PropTypes.object,
+      labelledby: PropTypes.string.isRequired,
+    };
+  }
+
+  [AUDIT_TYPE.CONTRAST](contrastRatio) {
+    return ColorContrastCheck(contrastRatio);
+  }
+
+  [AUDIT_TYPE.KEYBOARD](keyboardCheck) {
+    return KeyboardCheck(keyboardCheck);
+  }
+
+  [AUDIT_TYPE.TEXT_LABEL](textLabelCheck) {
+    return TextLabelCheck(textLabelCheck);
+  }
+
+  render() {
+    const { audit, labelledby } = this.props;
+    if (!audit) {
+      return EmptyChecks();
+    }
+
+    const items = [];
+    for (const name in audit) {
+      // There are going to be various audit reports for this object, sent by the server.
+      // Iterate over them and delegate rendering to the method with the corresponding
+      // name.
+      if (audit[name] && this[name]) {
+        items.push({
+          component: this[name](audit[name]),
+          className: name,
+          key: name,
+        });
+      }
+    }
+
+    if (items.length === 0) {
+      return EmptyChecks();
+    }
+
+    return div(
+      {
+        className: "checks",
+        role: "presentation",
+        tabIndex: "-1",
+      },
+      List({ items, labelledby })
+    );
+  }
+}
+
+const mapStateToProps = ({ details, ui }) => {
+  const { audit } = details;
+  if (!audit) {
+    return {};
+  }
+
+  return { audit };
+};
+
+module.exports = connect(mapStateToProps)(Checks);
diff --git a/devtools/client/accessibility/components/ColorContrastAccessibility.js b/devtools/client/accessibility/components/ColorContrastAccessibility.js
new file mode 100644
index 0000000000..117ab67593
--- /dev/null
+++ b/devtools/client/accessibility/components/ColorContrastAccessibility.js
@@ -0,0 +1,229 @@
+/* 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/. */
+
+"use strict";
+
+const {
+  Component,
+  createFactory,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  div,
+  span,
+  h3,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+const LearnMoreLink = createFactory(
+  require("resource://devtools/client/accessibility/components/LearnMoreLink.js")
+);
+
+const {
+  A11Y_CONTRAST_LEARN_MORE_LINK,
+} = require("resource://devtools/client/accessibility/constants.js");
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+
+/**
+ * Component that renders a colour contrast value along with a swatch preview of what the
+ * text and background colours are.
+ */
+class ContrastValueClass extends Component {
+  static get propTypes() {
+    return {
+      backgroundColor: PropTypes.array.isRequired,
+      color: PropTypes.array.isRequired,
+      value: PropTypes.number.isRequired,
+      score: PropTypes.string,
+    };
+  }
+
+  render() {
+    const { backgroundColor, color, value, score } = this.props;
+
+    const className = ["accessibility-contrast-value", score].join(" ");
+
+    return span(
+      {
+        className,
+        role: "presentation",
+        style: {
+          "--accessibility-contrast-color": `rgba(${color})`,
+          "--accessibility-contrast-bg": `rgba(${backgroundColor})`,
+        },
+      },
+      value.toFixed(2)
+    );
+  }
+}
+
+const ContrastValue = createFactory(ContrastValueClass);
+
+/**
+ * Component that renders labeled colour contrast values together with the large text
+ * indiscator.
+ */
+class ColorContrastAccessibilityClass extends Component {
+  static get propTypes() {
+    return {
+      error: PropTypes.string,
+      isLargeText: PropTypes.bool.isRequired,
+      color: PropTypes.array.isRequired,
+      value: PropTypes.number,
+      min: PropTypes.number,
+      max: PropTypes.number,
+      backgroundColor: PropTypes.array,
+      backgroundColorMin: PropTypes.array,
+      backgroundColorMax: PropTypes.array,
+      score: PropTypes.string,
+      scoreMin: PropTypes.string,
+      scoreMax: PropTypes.string,
+    };
+  }
+
+  render() {
+    const {
+      error,
+      isLargeText,
+      color,
+      value,
+      backgroundColor,
+      score,
+      min,
+      backgroundColorMin,
+      scoreMin,
+      max,
+      backgroundColorMax,
+      scoreMax,
+    } = this.props;
+
+    const children = [];
+
+    if (error) {
+      children.push(
+        span(
+          {
+            className: "accessibility-color-contrast-error",
+            role: "presentation",
+          },
+          L10N.getStr("accessibility.contrast.error")
+        )
+      );
+
+      return div(
+        {
+          role: "presentation",
+          tabIndex: "-1",
+          className: "accessibility-color-contrast",
+        },
+        ...children
+      );
+    }
+
+    if (value) {
+      children.push(ContrastValue({ score, color, backgroundColor, value }));
+    } else {
+      children.push(
+        ContrastValue({
+          score: scoreMin,
+          color,
+          backgroundColor: backgroundColorMin,
+          value: min,
+        }),
+        div({
+          role: "presentation",
+          tabIndex: "-1",
+          className: "accessibility-color-contrast-separator",
+        }),
+        ContrastValue({
+          score: scoreMax,
+          color,
+          backgroundColor: backgroundColorMax,
+          value: max,
+        })
+      );
+    }
+
+    if (isLargeText) {
+      children.push(
+        span(
+          {
+            className: "accessibility-color-contrast-large-text",
+            role: "presentation",
+            title: L10N.getStr("accessibility.contrast.large.title"),
+          },
+          L10N.getStr("accessibility.contrast.large.text")
+        )
+      );
+    }
+
+    return div(
+      {
+        role: "presentation",
+        tabIndex: "-1",
+        className: "accessibility-color-contrast",
+      },
+      ...children
+    );
+  }
+}
+
+const ColorContrastAccessibility = createFactory(
+  ColorContrastAccessibilityClass
+);
+
+class ContrastAnnotationClass extends Component {
+  static get propTypes() {
+    return {
+      score: PropTypes.string,
+    };
+  }
+
+  render() {
+    const { score } = this.props;
+
+    return LearnMoreLink({
+      className: "accessibility-check-annotation",
+      href: A11Y_CONTRAST_LEARN_MORE_LINK,
+      learnMoreStringKey: "accessibility.learnMore",
+      l10n: L10N,
+      messageStringKey: `accessibility.contrast.annotation.${score}`,
+    });
+  }
+}
+
+const ContrastAnnotation = createFactory(ContrastAnnotationClass);
+
+class ColorContrastCheck extends Component {
+  static get propTypes() {
+    return {
+      error: PropTypes.string.isRequired,
+    };
+  }
+
+  render() {
+    const { error } = this.props;
+
+    return div(
+      {
+        role: "presentation",
+        tabIndex: "-1",
+        className: "accessibility-check",
+      },
+      h3(
+        {
+          className: "accessibility-check-header",
+        },
+        L10N.getStr("accessibility.contrast.header")
+      ),
+      ColorContrastAccessibility(this.props),
+      !error && ContrastAnnotation(this.props)
+    );
+  }
+}
+
+module.exports = {
+  ColorContrastAccessibility: ColorContrastAccessibilityClass,
+  ColorContrastCheck,
+};
diff --git a/devtools/client/accessibility/components/ContrastBadge.js b/devtools/client/accessibility/components/ContrastBadge.js
new file mode 100644
index 0000000000..ee37958f1e
--- /dev/null
+++ b/devtools/client/accessibility/components/ContrastBadge.js
@@ -0,0 +1,55 @@
+/* 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/. */
+"use strict";
+
+// React
+const {
+  createFactory,
+  PureComponent,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+
+const {
+  accessibility: { SCORES },
+} = require("resource://devtools/shared/constants.js");
+
+loader.lazyGetter(this, "Badge", () =>
+  createFactory(
+    require("resource://devtools/client/accessibility/components/Badge.js")
+  )
+);
+
+/**
+ * Component for rendering a badge for contrast accessibliity check
+ * failures association with a given accessibility object in the accessibility
+ * tree.
+ */
+class ContrastBadge extends PureComponent {
+  static get propTypes() {
+    return {
+      error: PropTypes.string,
+      score: PropTypes.string,
+    };
+  }
+
+  render() {
+    const { error, score } = this.props;
+    if (error || score !== SCORES.FAIL) {
+      return null;
+    }
+
+    return Badge({
+      score,
+      label: L10N.getStr("accessibility.badge.contrast"),
+      ariaLabel: L10N.getStr("accessibility.badge.contrast.warning"),
+      tooltip: L10N.getStr("accessibility.badge.contrast.tooltip"),
+    });
+  }
+}
+
+module.exports = ContrastBadge;
diff --git a/devtools/client/accessibility/components/Description.js b/devtools/client/accessibility/components/Description.js
new file mode 100644
index 0000000000..a31dbcbfa6
--- /dev/null
+++ b/devtools/client/accessibility/components/Description.js
@@ -0,0 +1,56 @@
+/* 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/. */
+"use strict";
+
+// React & Redux
+const {
+  createFactory,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const {
+  div,
+  p,
+  img,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+const LearnMoreLink = createFactory(
+  require("resource://devtools/client/accessibility/components/LearnMoreLink.js")
+);
+
+// Localization
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+
+const {
+  A11Y_LEARN_MORE_LINK,
+} = require("resource://devtools/client/accessibility/constants.js");
+
+/**
+ * Landing UI for the accessibility panel when Accessibility features are
+ * deactivated.
+ */
+function Description() {
+  return div(
+    { className: "description", role: "presentation", tabIndex: "-1" },
+    div(
+      { className: "general", role: "presentation", tabIndex: "-1" },
+      img({
+        src: "chrome://devtools/skin/images/accessibility.svg",
+        alt: L10N.getStr("accessibility.logo"),
+      }),
+      div(
+        { role: "presentation", tabIndex: "-1" },
+        LearnMoreLink({
+          href: A11Y_LEARN_MORE_LINK,
+          learnMoreStringKey: "accessibility.learnMore",
+          l10n: L10N,
+          messageStringKey: "accessibility.description.general.p1",
+        }),
+        p({}, L10N.getStr("accessibility.enable.disabledTitle"))
+      )
+    )
+  );
+}
+
+// Exports from this module
+exports.Description = Description;
diff --git a/devtools/client/accessibility/components/DisplayTabbingOrder.js b/devtools/client/accessibility/components/DisplayTabbingOrder.js
new file mode 100644
index 0000000000..f6e3fdf453
--- /dev/null
+++ b/devtools/client/accessibility/components/DisplayTabbingOrder.js
@@ -0,0 +1,79 @@
+/* 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/. */
+"use strict";
+
+// React
+const {
+  PureComponent,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const {
+  label,
+  input,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+
+const {
+  connect,
+} = require("resource://devtools/client/shared/vendor/react-redux.js");
+const {
+  updateDisplayTabbingOrder,
+} = require("resource://devtools/client/accessibility/actions/ui.js");
+
+class DisplayTabbingOrder extends PureComponent {
+  static get propTypes() {
+    return {
+      dispatch: PropTypes.func.isRequired,
+      tabbingOrderDisplayed: PropTypes.bool.isRequired,
+    };
+  }
+
+  constructor(props) {
+    super(props);
+
+    this.state = {
+      disabled: false,
+    };
+
+    this.onChange = this.onChange.bind(this);
+  }
+
+  async onChange() {
+    const { dispatch, tabbingOrderDisplayed } = this.props;
+
+    this.setState({ disabled: true });
+    await dispatch(updateDisplayTabbingOrder(!tabbingOrderDisplayed));
+    this.setState({ disabled: false });
+  }
+
+  render() {
+    const { tabbingOrderDisplayed } = this.props;
+    return label(
+      {
+        className:
+          "accessibility-tabbing-order devtools-checkbox-label devtools-ellipsis-text",
+        htmlFor: "devtools-display-tabbing-order-checkbox",
+        title: L10N.getStr("accessibility.toolbar.displayTabbingOrder.tooltip"),
+      },
+      input({
+        id: "devtools-display-tabbing-order-checkbox",
+        className: "devtools-checkbox",
+        type: "checkbox",
+        checked: tabbingOrderDisplayed,
+        disabled: this.state.disabled,
+        onChange: this.onChange,
+      }),
+      L10N.getStr("accessibility.toolbar.displayTabbingOrder.label")
+    );
+  }
+}
+
+const mapStateToProps = ({ ui: { tabbingOrderDisplayed } }) => ({
+  tabbingOrderDisplayed,
+});
+
+module.exports = connect(mapStateToProps)(DisplayTabbingOrder);
diff --git a/devtools/client/accessibility/components/KeyboardBadge.js b/devtools/client/accessibility/components/KeyboardBadge.js
new file mode 100644
index 0000000000..ac6b6b8841
--- /dev/null
+++ b/devtools/client/accessibility/components/KeyboardBadge.js
@@ -0,0 +1,56 @@
+/* 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/. */
+
+"use strict";
+
+// React
+const {
+  createFactory,
+  PureComponent,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+
+const {
+  accessibility: {
+    SCORES: { BEST_PRACTICES, FAIL, WARNING },
+  },
+} = require("resource://devtools/shared/constants.js");
+
+loader.lazyGetter(this, "Badge", () =>
+  createFactory(
+    require("resource://devtools/client/accessibility/components/Badge.js")
+  )
+);
+
+/**
+ * Component for rendering a badge for keyboard accessibliity check failures
+ * association with a given accessibility object in the accessibility tree.
+ */
+class KeyboardBadge extends PureComponent {
+  static get propTypes() {
+    return {
+      error: PropTypes.string,
+      score: PropTypes.string,
+    };
+  }
+
+  render() {
+    const { error, score } = this.props;
+    if (error || ![BEST_PRACTICES, FAIL, WARNING].includes(score)) {
+      return null;
+    }
+
+    return Badge({
+      score,
+      label: L10N.getStr("accessibility.badge.keyboard"),
+      tooltip: L10N.getStr("accessibility.badge.keyboard.tooltip"),
+    });
+  }
+}
+
+module.exports = KeyboardBadge;
diff --git a/devtools/client/accessibility/components/KeyboardCheck.js b/devtools/client/accessibility/components/KeyboardCheck.js
new file mode 100644
index 0000000000..0109dd22b0
--- /dev/null
+++ b/devtools/client/accessibility/components/KeyboardCheck.js
@@ -0,0 +1,94 @@
+/* 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/. */
+"use strict";
+
+// React
+const {
+  createFactory,
+  PureComponent,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const ReactDOM = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+
+const Check = createFactory(
+  require("resource://devtools/client/accessibility/components/Check.js")
+);
+
+const {
+  A11Y_KEYBOARD_LINKS,
+} = require("resource://devtools/client/accessibility/constants.js");
+const {
+  accessibility: {
+    AUDIT_TYPE: { KEYBOARD },
+    ISSUE_TYPE: {
+      [KEYBOARD]: {
+        FOCUSABLE_NO_SEMANTICS,
+        FOCUSABLE_POSITIVE_TABINDEX,
+        INTERACTIVE_NO_ACTION,
+        INTERACTIVE_NOT_FOCUSABLE,
+        MOUSE_INTERACTIVE_ONLY,
+        NO_FOCUS_VISIBLE,
+      },
+    },
+  },
+} = require("resource://devtools/shared/constants.js");
+
+/**
+ * A map from text label issues to annotation component properties.
+ */
+const ISSUE_TO_ANNOTATION_MAP = {
+  [FOCUSABLE_NO_SEMANTICS]: {
+    href: A11Y_KEYBOARD_LINKS.FOCUSABLE_NO_SEMANTICS,
+    l10nId: "accessibility-keyboard-issue-semantics",
+  },
+  [FOCUSABLE_POSITIVE_TABINDEX]: {
+    href: A11Y_KEYBOARD_LINKS.FOCUSABLE_POSITIVE_TABINDEX,
+    l10nId: "accessibility-keyboard-issue-tabindex",
+    args: {
+      get code() {
+        return ReactDOM.code({}, "tabindex");
+      },
+    },
+  },
+  [INTERACTIVE_NO_ACTION]: {
+    href: A11Y_KEYBOARD_LINKS.INTERACTIVE_NO_ACTION,
+    l10nId: "accessibility-keyboard-issue-action",
+  },
+  [INTERACTIVE_NOT_FOCUSABLE]: {
+    href: A11Y_KEYBOARD_LINKS.INTERACTIVE_NOT_FOCUSABLE,
+    l10nId: "accessibility-keyboard-issue-focusable",
+  },
+  [MOUSE_INTERACTIVE_ONLY]: {
+    href: A11Y_KEYBOARD_LINKS.MOUSE_INTERACTIVE_ONLY,
+    l10nId: "accessibility-keyboard-issue-mouse-only",
+  },
+  [NO_FOCUS_VISIBLE]: {
+    href: A11Y_KEYBOARD_LINKS.NO_FOCUS_VISIBLE,
+    l10nId: "accessibility-keyboard-issue-focus-visible",
+  },
+};
+
+/**
+ * Component for rendering a check for text label accessibliity check failures,
+ * warnings and best practices suggestions association with a given
+ * accessibility object in the accessibility tree.
+ */
+class KeyboardCheck extends PureComponent {
+  static get propTypes() {
+    return {
+      issue: PropTypes.string.isRequired,
+      score: PropTypes.string.isRequired,
+    };
+  }
+
+  render() {
+    return Check({
+      ...this.props,
+      getAnnotation: issue => ISSUE_TO_ANNOTATION_MAP[issue],
+      id: "accessibility-keyboard-header",
+    });
+  }
+}
+
+module.exports = KeyboardCheck;
diff --git a/devtools/client/accessibility/components/LearnMoreLink.js b/devtools/client/accessibility/components/LearnMoreLink.js
new file mode 100644
index 0000000000..2a21df4ea5
--- /dev/null
+++ b/devtools/client/accessibility/components/LearnMoreLink.js
@@ -0,0 +1,76 @@
+/* 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/. */
+
+"use strict";
+
+const {
+  Component,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  p,
+  a,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+
+const { openDocLink } = require("resource://devtools/client/shared/link.js");
+
+/**
+ * Localization friendly component for rendering a block of text with a "Learn more" link
+ * as a part of it.
+ */
+class LearnMoreLink extends Component {
+  static get propTypes() {
+    return {
+      className: PropTypes.string,
+      href: PropTypes.string,
+      learnMoreStringKey: PropTypes.string.isRequired,
+      l10n: PropTypes.object.isRequired,
+      messageStringKey: PropTypes.string.isRequired,
+      onClick: PropTypes.func,
+    };
+  }
+
+  static get defaultProps() {
+    return {
+      href: "#",
+      learnMoreStringKey: null,
+      l10n: null,
+      messageStringKey: null,
+      onClick: LearnMoreLink.openDocOnClick,
+    };
+  }
+
+  static openDocOnClick(event) {
+    event.preventDefault();
+    openDocLink(event.target.href);
+  }
+
+  render() {
+    const {
+      className,
+      href,
+      learnMoreStringKey,
+      l10n,
+      messageStringKey,
+      onClick,
+    } = this.props;
+    const learnMoreString = l10n.getStr(learnMoreStringKey);
+    const messageString = l10n.getFormatStr(messageStringKey, learnMoreString);
+
+    // Split the paragraph string with the link as a separator, and include the link into
+    // results.
+    const re = new RegExp(`(\\b${learnMoreString}\\b)`);
+    const contents = messageString.split(re);
+    contents[1] = a({ className: "link", href, onClick }, contents[1]);
+
+    return p(
+      {
+        className,
+      },
+      ...contents
+    );
+  }
+}
+
+module.exports = LearnMoreLink;
diff --git a/devtools/client/accessibility/components/MainFrame.js b/devtools/client/accessibility/components/MainFrame.js
new file mode 100644
index 0000000000..d918dc7be0
--- /dev/null
+++ b/devtools/client/accessibility/components/MainFrame.js
@@ -0,0 +1,245 @@
+/* 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/. */
+"use strict";
+
+// React & Redux
+const {
+  Component,
+  createFactory,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const {
+  span,
+  div,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  connect,
+} = require("resource://devtools/client/shared/vendor/react-redux.js");
+const {
+  enable,
+  reset,
+  updateCanBeEnabled,
+  updateCanBeDisabled,
+} = require("resource://devtools/client/accessibility/actions/ui.js");
+
+// Localization
+const FluentReact = require("resource://devtools/client/shared/vendor/fluent-react.js");
+const LocalizationProvider = createFactory(FluentReact.LocalizationProvider);
+
+// Constants
+const {
+  SIDEBAR_WIDTH,
+  PORTRAIT_MODE_WIDTH,
+} = require("resource://devtools/client/accessibility/constants.js");
+
+// Accessibility Panel
+const AccessibilityTree = createFactory(
+  require("resource://devtools/client/accessibility/components/AccessibilityTree.js")
+);
+const AuditProgressOverlay = createFactory(
+  require("resource://devtools/client/accessibility/components/AuditProgressOverlay.js")
+);
+const Description = createFactory(
+  require("resource://devtools/client/accessibility/components/Description.js")
+    .Description
+);
+const RightSidebar = createFactory(
+  require("resource://devtools/client/accessibility/components/RightSidebar.js")
+);
+const Toolbar = createFactory(
+  require("resource://devtools/client/accessibility/components/Toolbar.js")
+    .Toolbar
+);
+const SplitBox = createFactory(
+  require("resource://devtools/client/shared/components/splitter/SplitBox.js")
+);
+
+/**
+ * Renders basic layout of the Accessibility panel. The Accessibility panel
+ * content consists of two main parts: tree and sidebar.
+ */
+class MainFrame extends Component {
+  static get propTypes() {
+    return {
+      fluentBundles: PropTypes.array.isRequired,
+      enabled: PropTypes.bool.isRequired,
+      dispatch: PropTypes.func.isRequired,
+      auditing: PropTypes.array.isRequired,
+      supports: PropTypes.object,
+      toolbox: PropTypes.object.isRequired,
+      getAccessibilityTreeRoot: PropTypes.func.isRequired,
+      startListeningForAccessibilityEvents: PropTypes.func.isRequired,
+      stopListeningForAccessibilityEvents: PropTypes.func.isRequired,
+      audit: PropTypes.func.isRequired,
+      simulate: PropTypes.func,
+      enableAccessibility: PropTypes.func.isRequired,
+      resetAccessiblity: PropTypes.func.isRequired,
+      startListeningForLifecycleEvents: PropTypes.func.isRequired,
+      stopListeningForLifecycleEvents: PropTypes.func.isRequired,
+      startListeningForParentLifecycleEvents: PropTypes.func.isRequired,
+      stopListeningForParentLifecycleEvents: PropTypes.func.isRequired,
+      highlightAccessible: PropTypes.func.isRequired,
+      unhighlightAccessible: PropTypes.func.isRequired,
+    };
+  }
+
+  constructor(props) {
+    super(props);
+
+    this.resetAccessibility = this.resetAccessibility.bind(this);
+    this.onPanelWindowResize = this.onPanelWindowResize.bind(this);
+    this.onCanBeEnabledChange = this.onCanBeEnabledChange.bind(this);
+    this.onCanBeDisabledChange = this.onCanBeDisabledChange.bind(this);
+  }
+
+  // FIXME: https://bugzilla.mozilla.org/show_bug.cgi?id=1774507
+  UNSAFE_componentWillMount() {
+    this.props.startListeningForLifecycleEvents({
+      init: this.resetAccessibility,
+      shutdown: this.resetAccessibility,
+    });
+    this.props.startListeningForParentLifecycleEvents({
+      "can-be-enabled-change": this.onCanBeEnabledChange,
+      "can-be-disabled-change": this.onCanBeDisabledChange,
+    });
+    this.props.startListeningForAccessibilityEvents({
+      "top-level-document-ready": this.resetAccessibility,
+    });
+    window.addEventListener("resize", this.onPanelWindowResize, true);
+  }
+
+  componentWillUnmount() {
+    this.props.stopListeningForLifecycleEvents({
+      init: this.resetAccessibility,
+      shutdown: this.resetAccessibility,
+    });
+    this.props.stopListeningForParentLifecycleEvents({
+      "can-be-enabled-change": this.onCanBeEnabledChange,
+      "can-be-disabled-change": this.onCanBeDisabledChange,
+    });
+    this.props.stopListeningForAccessibilityEvents({
+      "top-level-document-ready": this.resetAccessibility,
+    });
+    window.removeEventListener("resize", this.onPanelWindowResize, true);
+  }
+
+  resetAccessibility() {
+    const { dispatch, resetAccessiblity, supports } = this.props;
+    dispatch(reset(resetAccessiblity, supports));
+  }
+
+  onCanBeEnabledChange(canBeEnabled) {
+    const { enableAccessibility, dispatch } = this.props;
+    dispatch(updateCanBeEnabled(canBeEnabled));
+    if (canBeEnabled) {
+      dispatch(enable(enableAccessibility));
+    }
+  }
+
+  onCanBeDisabledChange(canBeDisabled) {
+    this.props.dispatch(updateCanBeDisabled(canBeDisabled));
+  }
+
+  get useLandscapeMode() {
+    const { clientWidth } = document.getElementById("content");
+    return clientWidth > PORTRAIT_MODE_WIDTH;
+  }
+
+  /**
+   * If panel width is less than PORTRAIT_MODE_WIDTH px, the splitter changes
+   * its mode to `horizontal` to support portrait view.
+   */
+  onPanelWindowResize() {
+    if (this.refs.splitBox) {
+      this.refs.splitBox.setState({ vert: this.useLandscapeMode });
+    }
+  }
+
+  /**
+   * Render Accessibility panel content
+   */
+  render() {
+    const {
+      fluentBundles,
+      enabled,
+      auditing,
+      simulate,
+      toolbox,
+      getAccessibilityTreeRoot,
+      startListeningForAccessibilityEvents,
+      stopListeningForAccessibilityEvents,
+      audit,
+      highlightAccessible,
+      unhighlightAccessible,
+    } = this.props;
+
+    if (!enabled) {
+      return Description();
+    }
+
+    // Audit is currently running.
+    const isAuditing = !!auditing.length;
+
+    return LocalizationProvider(
+      { bundles: fluentBundles },
+      div(
+        { className: "mainFrame", role: "presentation", tabIndex: "-1" },
+        Toolbar({
+          audit,
+          simulate,
+          toolboxDoc: toolbox.doc,
+        }),
+        isAuditing && AuditProgressOverlay(),
+        span(
+          {
+            "aria-hidden": isAuditing,
+            role: "presentation",
+            style: { display: "contents" },
+          },
+          SplitBox({
+            ref: "splitBox",
+            initialSize: SIDEBAR_WIDTH,
+            minSize: "10%",
+            maxSize: "80%",
+            splitterSize: 1,
+            endPanelControl: true,
+            startPanel: div(
+              {
+                className: "main-panel",
+                role: "presentation",
+                tabIndex: "-1",
+              },
+              AccessibilityTree({
+                toolboxDoc: toolbox.doc,
+                getAccessibilityTreeRoot,
+                startListeningForAccessibilityEvents,
+                stopListeningForAccessibilityEvents,
+                highlightAccessible,
+                unhighlightAccessible,
+              })
+            ),
+            endPanel: RightSidebar({
+              highlightAccessible,
+              unhighlightAccessible,
+              toolbox,
+            }),
+            vert: this.useLandscapeMode,
+          })
+        )
+      )
+    );
+  }
+}
+
+const mapStateToProps = ({
+  ui: { enabled, supports },
+  audit: { auditing },
+}) => ({
+  enabled,
+  supports,
+  auditing,
+});
+
+// Exports from this module
+module.exports = connect(mapStateToProps)(MainFrame);
diff --git a/devtools/client/accessibility/components/RightSidebar.js b/devtools/client/accessibility/components/RightSidebar.js
new file mode 100644
index 0000000000..f525b96294
--- /dev/null
+++ b/devtools/client/accessibility/components/RightSidebar.js
@@ -0,0 +1,67 @@
+/* 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/. */
+"use strict";
+
+// React
+const {
+  createFactory,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const {
+  div,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+const Accessible = createFactory(
+  require("resource://devtools/client/accessibility/components/Accessible.js")
+);
+const Accordion = createFactory(
+  require("resource://devtools/client/shared/components/Accordion.js")
+);
+const Checks = createFactory(
+  require("resource://devtools/client/accessibility/components/Checks.js")
+);
+
+// Component that is responsible for rendering accessible panel's sidebar.
+function RightSidebar({ highlightAccessible, unhighlightAccessible, toolbox }) {
+  const propertiesID = "accessibility-properties";
+  const checksID = "accessibility-checks";
+
+  return div(
+    {
+      className: "right-sidebar",
+      role: "presentation",
+      tabIndex: "-1",
+    },
+    Accordion({
+      items: [
+        {
+          className: "checks",
+          component: Checks,
+          componentProps: { labelledby: `${checksID}-header` },
+          header: L10N.getStr("accessibility.checks"),
+          id: checksID,
+          opened: true,
+        },
+        {
+          className: "accessible",
+          component: Accessible,
+          componentProps: {
+            highlightAccessible,
+            unhighlightAccessible,
+            toolboxHighlighter: toolbox.getHighlighter(),
+            toolbox,
+            labelledby: `${propertiesID}-header`,
+          },
+          header: L10N.getStr("accessibility.properties"),
+          id: propertiesID,
+          opened: true,
+        },
+      ],
+    })
+  );
+}
+
+module.exports = RightSidebar;
diff --git a/devtools/client/accessibility/components/SimulationMenuButton.js b/devtools/client/accessibility/components/SimulationMenuButton.js
new file mode 100644
index 0000000000..6fd21f4cc8
--- /dev/null
+++ b/devtools/client/accessibility/components/SimulationMenuButton.js
@@ -0,0 +1,167 @@
+/* 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/. */
+"use strict";
+
+/* global gTelemetry */
+
+// React
+const {
+  createFactory,
+  Component,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const {
+  hr,
+  span,
+  div,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+const {
+  connect,
+} = require("resource://devtools/client/shared/vendor/react-redux.js");
+const MenuButton = createFactory(
+  require("resource://devtools/client/shared/components/menu/MenuButton.js")
+);
+const { openDocLink } = require("resource://devtools/client/shared/link.js");
+const {
+  A11Y_SIMULATION_DOCUMENTATION_LINK,
+} = require("resource://devtools/client/accessibility/constants.js");
+const {
+  accessibility: { SIMULATION_TYPE },
+} = require("resource://devtools/shared/constants.js");
+const actions = require("resource://devtools/client/accessibility/actions/simulation.js");
+
+loader.lazyGetter(this, "MenuItem", function () {
+  return createFactory(
+    require("resource://devtools/client/shared/components/menu/MenuItem.js")
+  );
+});
+loader.lazyGetter(this, "MenuList", function () {
+  return createFactory(
+    require("resource://devtools/client/shared/components/menu/MenuList.js")
+  );
+});
+
+const TELEMETRY_SIMULATION_ACTIVATED =
+  "devtools.accessibility.simulation_activated";
+const SIMULATION_MENU_LABELS = {
+  NONE: "accessibility.filter.none",
+  [SIMULATION_TYPE.ACHROMATOPSIA]: "accessibility.simulation.achromatopsia",
+  [SIMULATION_TYPE.PROTANOPIA]: "accessibility.simulation.protanopia",
+  [SIMULATION_TYPE.DEUTERANOPIA]: "accessibility.simulation.deuteranopia",
+  [SIMULATION_TYPE.TRITANOPIA]: "accessibility.simulation.tritanopia",
+  [SIMULATION_TYPE.CONTRAST_LOSS]: "accessibility.simulation.contrastLoss",
+  DOCUMENTATION: "accessibility.documentation.label",
+};
+
+class SimulationMenuButton extends Component {
+  static get propTypes() {
+    return {
+      simulate: PropTypes.func,
+      simulation: PropTypes.object.isRequired,
+      dispatch: PropTypes.func.isRequired,
+      toolboxDoc: PropTypes.object.isRequired,
+    };
+  }
+
+  constructor(props) {
+    super(props);
+
+    this.disableSimulation = this.disableSimulation.bind(this);
+  }
+
+  disableSimulation() {
+    const { dispatch, simulate: simulateFunc } = this.props;
+
+    dispatch(actions.simulate(simulateFunc));
+  }
+
+  toggleSimulation(simKey) {
+    const { dispatch, simulation, simulate: simulateFunc } = this.props;
+
+    if (!simulation[simKey]) {
+      if (gTelemetry) {
+        gTelemetry.keyedScalarAdd(TELEMETRY_SIMULATION_ACTIVATED, simKey, 1);
+      }
+
+      dispatch(actions.simulate(simulateFunc, [simKey]));
+      return;
+    }
+
+    this.disableSimulation();
+  }
+
+  render() {
+    const { simulation, toolboxDoc } = this.props;
+    const simulationMenuButtonId = "simulation-menu-button";
+    const toolbarLabelID = "accessibility-simulation-label";
+    const currSimulation = Object.entries(simulation).find(
+      simEntry => simEntry[1]
+    );
+
+    const items = [
+      // No simulation option
+      MenuItem({
+        key: "simulation-none",
+        label: L10N.getStr(SIMULATION_MENU_LABELS.NONE),
+        checked: !currSimulation,
+        onClick: this.disableSimulation,
+      }),
+      hr({ key: "hr-1" }),
+      // Simulation options
+      ...Object.keys(SIMULATION_TYPE).map(simType =>
+        MenuItem({
+          key: `simulation-${simType}`,
+          label: L10N.getStr(SIMULATION_MENU_LABELS[simType]),
+          checked: simulation[simType],
+          onClick: this.toggleSimulation.bind(this, simType),
+        })
+      ),
+      hr({ key: "hr-2" }),
+      // Documentation link
+      MenuItem({
+        className: "link",
+        key: "simulation-documentation",
+        label: L10N.getStr(SIMULATION_MENU_LABELS.DOCUMENTATION),
+        role: "link",
+        onClick: () => openDocLink(A11Y_SIMULATION_DOCUMENTATION_LINK),
+      }),
+    ];
+
+    return div(
+      {
+        role: "group",
+        className: "accessibility-simulation",
+        "aria-labelledby": toolbarLabelID,
+      },
+      span(
+        { id: toolbarLabelID, role: "presentation" },
+        L10N.getStr("accessibility.simulation")
+      ),
+      MenuButton(
+        {
+          id: simulationMenuButtonId,
+          menuId: simulationMenuButtonId + "-menu",
+          className: `devtools-button toolbar-menu-button simulation${
+            currSimulation ? " active" : ""
+          }`,
+          toolboxDoc,
+          label: L10N.getStr(
+            SIMULATION_MENU_LABELS[currSimulation ? currSimulation[0] : "NONE"]
+          ),
+        },
+        MenuList({}, items)
+      )
+    );
+  }
+}
+
+const mapStateToProps = ({ simulation }) => {
+  return { simulation };
+};
+
+// Exports from this module
+module.exports = connect(mapStateToProps)(SimulationMenuButton);
diff --git a/devtools/client/accessibility/components/TextLabelBadge.js b/devtools/client/accessibility/components/TextLabelBadge.js
new file mode 100644
index 0000000000..0ff54ef8e0
--- /dev/null
+++ b/devtools/client/accessibility/components/TextLabelBadge.js
@@ -0,0 +1,57 @@
+/* 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/. */
+
+"use strict";
+
+// React
+const {
+  createFactory,
+  PureComponent,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+
+const {
+  L10N,
+} = require("resource://devtools/client/accessibility/utils/l10n.js");
+
+const {
+  accessibility: {
+    SCORES: { BEST_PRACTICES, FAIL, WARNING },
+  },
+} = require("resource://devtools/shared/constants.js");
+
+loader.lazyGetter(this, "Badge", () =>
+  createFactory(
+    require("resource://devtools/client/accessibility/components/Badge.js")
+  )
+);
+
+/**
+ * Component for rendering a badge for text alternative accessibliity check
+ * failures association with a given accessibility object in the accessibility
+ * tree.
+ */
+class TextLabelBadge extends PureComponent {
+  static get propTypes() {
+    return {
+      error: PropTypes.string,
+      score: PropTypes.string,
+    };
+  }
+
+  render() {
+    const { error, score } = this.props;
+    if (error || ![BEST_PRACTICES, FAIL, WARNING].includes(score)) {
+      return null;
+    }
+
+    return Badge({
+      score,
+      label: L10N.getStr("accessibility.badge.textLabel"),
+      tooltip: L10N.getStr("accessibility.badge.textLabel.tooltip"),
+    });
+  }
+}
+
+module.exports = TextLabelBadge;
diff --git a/devtools/client/accessibility/components/TextLabelCheck.js b/devtools/client/accessibility/components/TextLabelCheck.js
new file mode 100644
index 0000000000..adfbb4b412
--- /dev/null
+++ b/devtools/client/accessibility/components/TextLabelCheck.js
@@ -0,0 +1,225 @@
+/* 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/. */
+"use strict";
+
+// React
+const {
+  createFactory,
+  PureComponent,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+const ReactDOM = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+
+const Check = createFactory(
+  require("resource://devtools/client/accessibility/components/Check.js")
+);
+
+const {
+  A11Y_TEXT_LABEL_LINKS,
+} = require("resource://devtools/client/accessibility/constants.js");
+const {
+  accessibility: {
+    AUDIT_TYPE: { TEXT_LABEL },
+    ISSUE_TYPE: {
+      [TEXT_LABEL]: {
+        AREA_NO_NAME_FROM_ALT,
+        DIALOG_NO_NAME,
+        DOCUMENT_NO_TITLE,
+        EMBED_NO_NAME,
+        FIGURE_NO_NAME,
+        FORM_FIELDSET_NO_NAME,
+        FORM_FIELDSET_NO_NAME_FROM_LEGEND,
+        FORM_NO_NAME,
+        FORM_NO_VISIBLE_NAME,
+        FORM_OPTGROUP_NO_NAME_FROM_LABEL,
+        FRAME_NO_NAME,
+        HEADING_NO_CONTENT,
+        HEADING_NO_NAME,
+        IFRAME_NO_NAME_FROM_TITLE,
+        IMAGE_NO_NAME,
+        INTERACTIVE_NO_NAME,
+        MATHML_GLYPH_NO_NAME,
+        TOOLBAR_NO_NAME,
+      },
+    },
+  },
+} = require("resource://devtools/shared/constants.js");
+
+/**
+ * A map from text label issues to annotation component properties.
+ */
+const ISSUE_TO_ANNOTATION_MAP = {
+  [AREA_NO_NAME_FROM_ALT]: {
+    href: A11Y_TEXT_LABEL_LINKS.AREA_NO_NAME_FROM_ALT,
+    l10nId: "accessibility-text-label-issue-area",
+    args: {
+      get code() {
+        return ReactDOM.code({}, "alt");
+      },
+      // Note: there is no way right now to use custom elements in privileged
+      // content. We have to use something like <div> since we can't provide
+      // three args with the same name.
+      get div() {
+        return ReactDOM.code({}, "area");
+      },
+      // Note: there is no way right now to use custom elements in privileged
+      // content. We have to use something like <span> since we can't provide
+      // three args with the same name.
+      get span() {
+        return ReactDOM.code({}, "href");
+      },
+    },
+  },
+  [DIALOG_NO_NAME]: {
+    href: A11Y_TEXT_LABEL_LINKS.DIALOG_NO_NAME,
+    l10nId: "accessibility-text-label-issue-dialog",
+  },
+  [DOCUMENT_NO_TITLE]: {
+    href: A11Y_TEXT_LABEL_LINKS.DOCUMENT_NO_TITLE,
+    l10nId: "accessibility-text-label-issue-document-title",
+    args: {
+      get code() {
+        return ReactDOM.code({}, "title");
+      },
+    },
+  },
+  [EMBED_NO_NAME]: {
+    href: A11Y_TEXT_LABEL_LINKS.EMBED_NO_NAME,
+    l10nId: "accessibility-text-label-issue-embed",
+  },
+  [FIGURE_NO_NAME]: {
+    href: A11Y_TEXT_LABEL_LINKS.FIGURE_NO_NAME,
+    l10nId: "accessibility-text-label-issue-figure",
+  },
+  [FORM_FIELDSET_NO_NAME]: {
+    href: A11Y_TEXT_LABEL_LINKS.FORM_FIELDSET_NO_NAME,
+    l10nId: "accessibility-text-label-issue-fieldset",
+    args: {
+      get code() {
+        return ReactDOM.code({}, "fieldset");
+      },
+    },
+  },
+  [FORM_FIELDSET_NO_NAME_FROM_LEGEND]: {
+    href: A11Y_TEXT_LABEL_LINKS.FORM_FIELDSET_NO_NAME_FROM_LEGEND,
+    l10nId: "accessibility-text-label-issue-fieldset-legend2",
+    args: {
+      get code() {
+        return ReactDOM.code({}, "legend");
+      },
+      // Note: there is no way right now to use custom elements in privileged
+      // content. We have to use something like <span> since we can't provide
+      // two args with the same name.
+      get span() {
+        return ReactDOM.code({}, "fieldset");
+      },
+    },
+  },
+  [FORM_NO_NAME]: {
+    href: A11Y_TEXT_LABEL_LINKS.FORM_NO_NAME,
+    l10nId: "accessibility-text-label-issue-form",
+  },
+  [FORM_NO_VISIBLE_NAME]: {
+    href: A11Y_TEXT_LABEL_LINKS.FORM_NO_VISIBLE_NAME,
+    l10nId: "accessibility-text-label-issue-form-visible",
+  },
+  [FORM_OPTGROUP_NO_NAME_FROM_LABEL]: {
+    href: A11Y_TEXT_LABEL_LINKS.FORM_OPTGROUP_NO_NAME_FROM_LABEL,
+    l10nId: "accessibility-text-label-issue-optgroup-label2",
+    args: {
+      get code() {
+        return ReactDOM.code({}, "label");
+      },
+      // Note: there is no way right now to use custom elements in privileged
+      // content. We have to use something like <span> since we can't provide
+      // two args with the same name.
+      get span() {
+        return ReactDOM.code({}, "optgroup");
+      },
+    },
+  },
+  [FRAME_NO_NAME]: {
+    href: A11Y_TEXT_LABEL_LINKS.FRAME_NO_NAME,
+    l10nId: "accessibility-text-label-issue-frame",
+    args: {
+      get code() {
+        return ReactDOM.code({}, "frame");
+      },
+    },
+  },
+  [HEADING_NO_CONTENT]: {
+    href: A11Y_TEXT_LABEL_LINKS.HEADING_NO_CONTENT,
+    l10nId: "accessibility-text-label-issue-heading-content",
+  },
+  [HEADING_NO_NAME]: {
+    href: A11Y_TEXT_LABEL_LINKS.HEADING_NO_NAME,
+    l10nId: "accessibility-text-label-issue-heading",
+  },
+  [IFRAME_NO_NAME_FROM_TITLE]: {
+    href: A11Y_TEXT_LABEL_LINKS.IFRAME_NO_NAME_FROM_TITLE,
+    l10nId: "accessibility-text-label-issue-iframe",
+    args: {
+      get code() {
+        return ReactDOM.code({}, "title");
+      },
+      // Note: there is no way right now to use custom elements in privileged
+      // content. We have to use something like <span> since we can't provide
+      // two args with the same name.
+      get span() {
+        return ReactDOM.code({}, "iframe");
+      },
+    },
+  },
+  [IMAGE_NO_NAME]: {
+    href: A11Y_TEXT_LABEL_LINKS.IMAGE_NO_NAME,
+    l10nId: "accessibility-text-label-issue-image",
+  },
+  [INTERACTIVE_NO_NAME]: {
+    href: A11Y_TEXT_LABEL_LINKS.INTERACTIVE_NO_NAME,
+    l10nId: "accessibility-text-label-issue-interactive",
+  },
+  [MATHML_GLYPH_NO_NAME]: {
+    href: A11Y_TEXT_LABEL_LINKS.MATHML_GLYPH_NO_NAME,
+    l10nId: "accessibility-text-label-issue-glyph",
+    args: {
+      get code() {
+        return ReactDOM.code({}, "alt");
+      },
+      // Note: there is no way right now to use custom elements in privileged
+      // content. We have to use something like <span> since we can't provide
+      // two args with the same name.
+      get span() {
+        return ReactDOM.code({}, "mglyph");
+      },
+    },
+  },
+  [TOOLBAR_NO_NAME]: {
+    href: A11Y_TEXT_LABEL_LINKS.TOOLBAR_NO_NAME,
+    l10nId: "accessibility-text-label-issue-toolbar",
+  },
+};
+
+/**
+ * Component for rendering a check for text label accessibliity check failures,
+ * warnings and best practices suggestions association with a given
+ * accessibility object in the accessibility tree.
+ */
+class TextLabelCheck extends PureComponent {
+  static get propTypes() {
+    return {
+      issue: PropTypes.string.isRequired,
+      score: PropTypes.string.isRequired,
+    };
+  }
+
+  render() {
+    return Check({
+      ...this.props,
+      getAnnotation: issue => ISSUE_TO_ANNOTATION_MAP[issue],
+      id: "accessibility-text-label-header",
+    });
+  }
+}
+
+module.exports = TextLabelCheck;
diff --git a/devtools/client/accessibility/components/Toolbar.js b/devtools/client/accessibility/components/Toolbar.js
new file mode 100644
index 0000000000..b5f27485ed
--- /dev/null
+++ b/devtools/client/accessibility/components/Toolbar.js
@@ -0,0 +1,74 @@
+/* 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/. */
+"use strict";
+
+// React
+const {
+  createFactory,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const {
+  div,
+} = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+const AccessibilityTreeFilter = createFactory(
+  require("resource://devtools/client/accessibility/components/AccessibilityTreeFilter.js")
+);
+const AccessibilityPrefs = createFactory(
+  require("resource://devtools/client/accessibility/components/AccessibilityPrefs.js")
+);
+loader.lazyGetter(this, "SimulationMenuButton", function () {
+  return createFactory(
+    require("resource://devtools/client/accessibility/components/SimulationMenuButton.js")
+  );
+});
+const DisplayTabbingOrder = createFactory(
+  require("resource://devtools/client/accessibility/components/DisplayTabbingOrder.js")
+);
+
+const {
+  connect,
+} = require("resource://devtools/client/shared/vendor/react-redux.js");
+
+function Toolbar({ audit, simulate, supportsTabbingOrder, toolboxDoc }) {
+  const optionalSimulationSection = simulate
+    ? [
+        div({
+          role: "separator",
+          className: "devtools-separator",
+        }),
+        SimulationMenuButton({ simulate, toolboxDoc }),
+      ]
+    : [];
+  const optionalDisplayTabbingOrderSection = supportsTabbingOrder
+    ? [
+        div({
+          role: "separator",
+          className: "devtools-separator",
+        }),
+        DisplayTabbingOrder(),
+      ]
+    : [];
+
+  return div(
+    {
+      className: "devtools-toolbar",
+      role: "toolbar",
+    },
+    AccessibilityTreeFilter({ audit, toolboxDoc }),
+    // Simulation section is shown if webrender is enabled
+    ...optionalSimulationSection,
+    ...optionalDisplayTabbingOrderSection,
+    AccessibilityPrefs({ toolboxDoc })
+  );
+}
+
+const mapStateToProps = ({
+  ui: {
+    supports: { tabbingOrder },
+  },
+}) => ({
+  supportsTabbingOrder: tabbingOrder,
+});
+
+// Exports from this module
+exports.Toolbar = connect(mapStateToProps)(Toolbar);
diff --git a/devtools/client/accessibility/components/moz.build b/devtools/client/accessibility/components/moz.build
new file mode 100644
index 0000000000..23e01d42c6
--- /dev/null
+++ b/devtools/client/accessibility/components/moz.build
@@ -0,0 +1,33 @@
+# 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/.
+
+DevToolsModules(
+    "AccessibilityPrefs.js",
+    "AccessibilityRow.js",
+    "AccessibilityRowValue.js",
+    "AccessibilityTree.js",
+    "AccessibilityTreeFilter.js",
+    "Accessible.js",
+    "AuditController.js",
+    "AuditFilter.js",
+    "AuditProgressOverlay.js",
+    "Badge.js",
+    "Badges.js",
+    "Button.js",
+    "Check.js",
+    "Checks.js",
+    "ColorContrastAccessibility.js",
+    "ContrastBadge.js",
+    "Description.js",
+    "DisplayTabbingOrder.js",
+    "KeyboardBadge.js",
+    "KeyboardCheck.js",
+    "LearnMoreLink.js",
+    "MainFrame.js",
+    "RightSidebar.js",
+    "SimulationMenuButton.js",
+    "TextLabelBadge.js",
+    "TextLabelCheck.js",
+    "Toolbar.js",
+)