--- a/devtools/client/aboutdebugging-new/aboutdebugging.css
+++ b/devtools/client/aboutdebugging-new/aboutdebugging.css
@@ -1,20 +1,20 @@
 /* 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/. */
 
 @import "resource://devtools/client/themes/variables.css";
 @import "resource://devtools/client/aboutdebugging-new/src/components/App.css";
 @import "resource://devtools/client/aboutdebugging-new/src/components/Sidebar.css";
-@import "resource://devtools/client/aboutdebugging-new/src/components/runtime/RuntimeItem.css";
+@import "resource://devtools/client/aboutdebugging-new/src/components/SidebarItem.css";
 
 :root {
-  --runtime-item-icon-color: var(--grey-30);
-  --runtime-item-selected-color: var(--blue-55);
+  --sidebar-item-icon-color: var(--grey-30);
+  --sidebar-item-selected-color: var(--blue-55);
 }
 
 html, body {
   margin: 0;
   padding: 0;
 }
 
 ul {

--- a/devtools/client/aboutdebugging-new/src/components/Sidebar.js
+++ b/devtools/client/aboutdebugging-new/src/components/Sidebar.js
@@ -6,17 +6,17 @@
 
 const { createFactory, PureComponent } = require("devtools/client/shared/vendor/react");
 const dom = require("devtools/client/shared/vendor/react-dom-factories");
 const PropTypes = require("devtools/client/shared/vendor/react-prop-types");
 
 const ThisFirefox = require("../runtimes/this-firefox");
 
 const Runtime = require("../runtimes/runtime");
-const RuntimeItem = createFactory(require("./runtime/RuntimeItem"));
+const SidebarItem = createFactory(require("./SidebarItem"));
 
 class Sidebar extends PureComponent {
   static get propTypes() {
     return {
       selectedRuntime: PropTypes.instanceOf(Runtime),
       thisFirefox: PropTypes.instanceOf(ThisFirefox).isRequired,
     };
   }
@@ -25,17 +25,17 @@ class Sidebar extends PureComponent {
     const { selectedRuntime, thisFirefox } = this.props;
 
     return dom.section(
       {
         className: "sidebar",
       },
       dom.ul(
         {},
-        RuntimeItem({
+        SidebarItem({
           icon: thisFirefox.getIcon(),
           isSelected: thisFirefox === selectedRuntime,
           name: thisFirefox.getName(),
         })
       )
     );
   }
 }

rename from devtools/client/aboutdebugging-new/src/components/runtime/RuntimeItem.css
rename to devtools/client/aboutdebugging-new/src/components/SidebarItem.css
--- a/devtools/client/aboutdebugging-new/src/components/runtime/RuntimeItem.css
+++ b/devtools/client/aboutdebugging-new/src/components/SidebarItem.css
@@ -1,26 +1,26 @@
 /* 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/. */
 
-.runtime-item {
+.sidebar-item {
   align-items: center;
   display: flex;
   font-size: 20px;
   margin-inline-start: 24px;
 }
 
-.runtime-item__icon {
-  fill: var(--runtime-item-icon-color);
+.sidebar-item__icon {
+  fill: var(--sidebar-item-icon-color);
   height: 24px;
   margin-inline-end: 9px;
   width: 24px;
   -moz-context-properties: fill;
 }
 
-.runtime-item--selected {
-  color: var(--runtime-item-selected-color);
+.sidebar-item--selected {
+  color: var(--sidebar-item-selected-color);
 }
 
-.runtime-item__icon--selected {
-  fill: var(--runtime-item-selected-color);
+.sidebar-item__icon--selected {
+  fill: var(--sidebar-item-selected-color);
 }

rename from devtools/client/aboutdebugging-new/src/components/runtime/RuntimeItem.js
rename to devtools/client/aboutdebugging-new/src/components/SidebarItem.js
--- a/devtools/client/aboutdebugging-new/src/components/runtime/RuntimeItem.js
+++ b/devtools/client/aboutdebugging-new/src/components/SidebarItem.js
@@ -4,37 +4,37 @@
 
 "use strict";
 
 const { PureComponent } = require("devtools/client/shared/vendor/react");
 const dom = require("devtools/client/shared/vendor/react-dom-factories");
 const PropTypes = require("devtools/client/shared/vendor/react-prop-types");
 
 /**
- * This component shows the runtime as item in RuntimesPane.
+ * This component displays an item of the Sidebar component.
  */
-class RuntimeItem extends PureComponent {
+class SidebarItem extends PureComponent {
   static get propTypes() {
     return {
       icon: PropTypes.string.isRequired,
       isSelected: PropTypes.bool.isRequired,
       name: PropTypes.string.isRequired,
     };
   }
 
   render() {
     const { icon, isSelected, name } = this.props;
 
     return dom.li(
       {
-        className: "runtime-item" + (isSelected ? " runtime-item--selected" : ""),
+        className: "sidebar-item" + (isSelected ? " sidebar-item--selected" : ""),
       },
       dom.img({
-        className: "runtime-item__icon" +
-                   (isSelected ? " runtime-item__icon--selected" : ""),
+        className: "sidebar-item__icon" +
+                   (isSelected ? " sidebar-item__icon--selected" : ""),
         src: icon,
       }),
       name
     );
   }
 }
 
-module.exports = RuntimeItem;
+module.exports = SidebarItem;

--- a/devtools/client/aboutdebugging-new/src/components/moz.build
+++ b/devtools/client/aboutdebugging-new/src/components/moz.build
@@ -1,14 +1,12 @@
 # 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/.
 
-DIRS += [
-    'runtime',
-]
-
 DevToolsModules(
     'App.css',
     'App.js',
     'Sidebar.css',
-    'Sidebar.js'
+    'Sidebar.js',
+    'SidebarItem.css',
+    'SidebarItem.js',
 )

deleted file mode 100644
--- a/devtools/client/aboutdebugging-new/src/components/runtime/moz.build
+++ /dev/null
@@ -1,8 +0,0 @@
-# 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(
-    'RuntimeItem.css',
-    'RuntimeItem.js',
-)