From eeb0d1b2ac8ce6e5d3349a743dfb00d59c720f4f Mon Sep 17 00:00:00 2001
From: Adam Silverstein <adamjs@google.com>
Date: Mon, 17 Feb 2025 01:26:59 -0700
Subject: [PATCH] Improve display of error returned from the REST API when an
 unsupported image type is uploaded (#68788)

Co-authored-by: adamsilverstein <adamsilverstein@git.wordpress.org>
Co-authored-by: Mamaduka <mamaduka@git.wordpress.org>
---
 packages/media-utils/src/utils/upload-media.ts | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/packages/media-utils/src/utils/upload-media.ts b/packages/media-utils/src/utils/upload-media.ts
index 4b600f983c571..c7ba9d5dbb90b 100644
--- a/packages/media-utils/src/utils/upload-media.ts
+++ b/packages/media-utils/src/utils/upload-media.ts
@@ -143,9 +143,16 @@ export function uploadMedia( {
 			// Reset to empty on failure.
 			setAndUpdateFiles( index, null );
 
-			let message;
-			if ( error instanceof Error ) {
-				message = error.message;
+			let message: string;
+			if (
+				typeof error === 'object' &&
+				error !== null &&
+				'message' in error
+			) {
+				message =
+					typeof error.message === 'string'
+						? error.message
+						: String( error.message );
 			} else {
 				message = sprintf(
 					// translators: %s: file name