From a6425e64ea13ec3059d901ce6d526c430398c718 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andr=C3=A9?= <583546+oandregal@users.noreply.github.com>
Date: Fri, 18 Oct 2024 17:40:52 +0200
Subject: [PATCH] Cast string values to arrays

---
 packages/block-editor/src/store/selectors.js | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/packages/block-editor/src/store/selectors.js b/packages/block-editor/src/store/selectors.js
index df138f566a466b..e537c43651ea4a 100644
--- a/packages/block-editor/src/store/selectors.js
+++ b/packages/block-editor/src/store/selectors.js
@@ -1595,8 +1595,18 @@ const isBlockVisibleInTheInserter = (
 	checkedBlocks.add( blockName );
 
 	// If parent blocks are not visible, child blocks should be hidden too.
-	if ( Array.isArray( blockType?.parent ) ) {
-		return blockType.parent.some(
+	//
+	// In some scenarios, blockType.parent may be a string.
+	// A better approach would be sanitize parent in all the places that can be modified:
+	// block registration, processBlockType, filters, etc.
+	// In the meantime, this is a hotfix to prevent the editor from crashing.
+	const parent =
+		typeof blockType.parent === 'string' ||
+		blockType.parent instanceof String
+			? [ blockType.parent ]
+			: blockType.parent;
+	if ( Array.isArray( parent ) ) {
+		return parent.some(
 			( name ) =>
 				( blockName !== name &&
 					isBlockVisibleInTheInserter(
@@ -1610,6 +1620,7 @@ const isBlockVisibleInTheInserter = (
 				name === 'core/post-content'
 		);
 	}
+
 	return true;
 };