diff --git a/packages/rich-text/src/register-format-type.js b/packages/rich-text/src/register-format-type.js
index b271091cbe6a0..8ea19a97f595f 100644
--- a/packages/rich-text/src/register-format-type.js
+++ b/packages/rich-text/src/register-format-type.js
@@ -82,7 +82,10 @@ export function registerFormatType( name, settings ) {
 			richTextStore
 		).getFormatTypeForBareElement( settings.tagName );
 
-		if ( formatTypeForBareElement ) {
+		if (
+			formatTypeForBareElement &&
+			formatTypeForBareElement.name !== 'core/unknown'
+		) {
 			window.console.error(
 				`Format "${ formatTypeForBareElement.name }" is already registered to handle bare tag name "${ settings.tagName }".`
 			);
diff --git a/packages/rich-text/src/test/register-format-type.js b/packages/rich-text/src/test/register-format-type.js
index 0d044d28facfa..0f5c16eabf232 100644
--- a/packages/rich-text/src/test/register-format-type.js
+++ b/packages/rich-text/src/test/register-format-type.js
@@ -1,7 +1,7 @@
 /**
  * WordPress dependencies
  */
-import { select } from '@wordpress/data';
+import { dispatch, select } from '@wordpress/data';
 
 /**
  * Internal dependencies
@@ -11,10 +11,21 @@ import { unregisterFormatType } from '../unregister-format-type';
 import { getFormatType } from '../get-format-type';
 import { store as richTextStore } from '../store';
 
+const UNKNOWN_FORMAT = {
+	name: 'core/unknown',
+	title: 'Clear Unknown Formatting',
+	tagName: '*',
+	className: null,
+	edit: () => null,
+};
+
 describe( 'registerFormatType', () => {
 	beforeAll( () => {
 		// Initialize the rich-text store.
 		require( '../store' );
+
+		// Register "core/unknown" format
+		dispatch( richTextStore ).addFormatTypes( UNKNOWN_FORMAT );
 	} );
 
 	afterEach( () => {