Update: Move template areas into a panel.

packages/editor/src/components/sidebar/index.js

@@ -112,9 +112,7 @@ const SidebarContent = ( {
 				<Tabs.TabPanel tabId={ sidebars.document } focusable={ false }>
 					<PostSummary onActionPerformed={ onActionPerformed } />
 					<PluginDocumentSettingPanel.Slot />
-					{ renderingMode !== 'post-only' && (
-						<TemplateContentPanel />
-					) }
+					<TemplateContentPanel />
 					<PostTransformPanel />
 					<PostTaxonomiesPanel />
 					<PageAttributesPanel />

packages/editor/src/components/sidebar/post-summary.js

@@ -28,7 +28,6 @@ import BlogTitle from '../blog-title';
 import PostsPerPage from '../posts-per-page';
 import SiteDiscussion from '../site-discussion';
 import { store as editorStore } from '../../store';
-import TemplateAreas from '../template-areas';
 
 /**
  * Module Constants
@@ -82,7 +81,6 @@ export default function PostSummary( { onActionPerformed } ) {
 										<PostFormatPanel />
 										<PostStickyPanel />
 									</VStack>
-									<TemplateAreas />
 									{ fills }
 								</VStack>
 							) }

packages/editor/src/components/template-content-panel/index.js

@@ -13,6 +13,8 @@ import { __ } from '@wordpress/i18n';
  * Internal dependencies
  */
 import { unlock } from '../../lock-unlock';
+import { TEMPLATE_POST_TYPE } from '../../store/constants';
+import { store as editorStore } from '../../store';
 
 const { BlockQuickNavigation } = unlock( blockEditorPrivateApis );
 
@@ -22,11 +24,25 @@ const PAGE_CONTENT_BLOCKS = [
 	'core/post-title',
 ];
 
-export default function TemplateContentPanel() {
-	const clientIds = useSelect( ( select ) => {
+const TEMPLATE_PART_BLOCK = 'core/template-part';
+
+export default function TemplateContentPanel( { renderingMode } ) {
+	const { clientIds, postType } = useSelect( ( select ) => {
 		const { getBlocksByName } = select( blockEditorStore );
-		return getBlocksByName( PAGE_CONTENT_BLOCKS );
+		const { getCurrentPostType } = select( editorStore );
+		const _postType = getCurrentPostType();
+		return {
+			postType: _postType,
+			clientIds: getBlocksByName(
+				TEMPLATE_POST_TYPE === _postType
+					? TEMPLATE_PART_BLOCK
+					: PAGE_CONTENT_BLOCKS
+			),
+		};
 	}, [] );
+	if ( renderingMode !== 'post-only' && postType !== TEMPLATE_POST_TYPE ) {
+		return null;
+	}
 
 	return (
 		<PanelBody title={ __( 'Content' ) }>

packages/editor/src/store/private-selectors.js

@@ -19,8 +19,6 @@ import {
 	getRenderingMode,
 	__experimentalGetDefaultTemplatePartAreas,
 } from './selectors';
-import { TEMPLATE_PART_POST_TYPE } from './constants';
-import { getFilteredTemplatePartBlocks } from './utils/get-filtered-template-parts';
 
 const EMPTY_INSERTION_POINT = {
 	rootClientId: undefined,
@@ -112,26 +110,3 @@ export const getPostIcon = createRegistrySelector(
 		}
 	}
 );
-
-/**
- * Returns the template parts and their blocks for the current edited template.
- *
- * @param {Object} state Global application state.
- * @return {Array} Template parts and their blocks in an array.
- */
-export const getCurrentTemplateTemplateParts = createRegistrySelector(
-	( select ) => () => {
-		const templateParts = select( coreStore ).getEntityRecords(
-			'postType',
-			TEMPLATE_PART_POST_TYPE,
-			{ per_page: -1 }
-		);
-
-		const clientIds =
-			select( blockEditorStore ).getBlocksByName( 'core/template-part' );
-		const blocks =
-			select( blockEditorStore ).getBlocksByClientId( clientIds );
-
-		return getFilteredTemplatePartBlocks( blocks, templateParts );
-	}
-);

packages/editor/src/style.scss

@@ -51,6 +51,5 @@
 @import "./components/sidebar/style.scss";
 @import "./components/site-discussion/style.scss";
 @import "./components/table-of-contents/style.scss";
-@import "./components/template-areas/style.scss";
 @import "./components/text-editor/style.scss";
 @import "./components/visual-editor/style.scss";