From a39c4375c7960849bd448dfc85a734f9fe85ef37 Mon Sep 17 00:00:00 2001
From: Jon Surrell <sirreal@users.noreply.github.com>
Date: Fri, 6 Sep 2024 13:51:15 +0200
Subject: [PATCH] Only use a11y module in GUTENBERG_PLUGIN

---
 packages/interactivity-router/src/index.ts | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/packages/interactivity-router/src/index.ts b/packages/interactivity-router/src/index.ts
index 6c891ef159344d..5574ee925b1dfe 100644
--- a/packages/interactivity-router/src/index.ts
+++ b/packages/interactivity-router/src/index.ts
@@ -366,11 +366,19 @@ export const { state, actions } = store( 'core/router', {
  * @param ariaLive The politeness level for aria-live; default: 'polite'.
  */
 function a11yAnnounce( message: string, ariaLive?: 'polite' | 'assertive' ) {
-	import( '@wordpress/a11y' ).then(
-		( { speak } ) => speak( message, ariaLive ),
-		// Silence errors.
-		() => undefined
-	);
+	if ( globalThis.IS_GUTENBERG_PLUGIN ) {
+		import( '@wordpress/a11y' ).then(
+			( { speak } ) => speak( message, ariaLive ),
+			// Silence errors.
+			() => undefined
+		);
+	} else {
+		state.navigation.message =
+			// Announce that the page has been loaded. If the message is the
+			// same, we use a no-break space similar to the @wordpress/a11y
+			// package: https://github.com/WordPress/gutenberg/blob/c395242b8e6ee20f8b06c199e4fc2920d7018af1/packages/a11y/src/filter-message.js#L20-L26
+			message + ( state.navigation.message === message ? '\u00A0' : '' );
+	}
 }
 
 // Add click and prefetch to all links.