feat(prepareErrorMessage): treat error.data as object (#2601)

Author: Raubzeug

src/utils/prepareErrorMessage.ts

@@ -4,8 +4,16 @@ export function prepareErrorMessage(error: unknown) {
     }
 
     if (error && typeof error === 'object') {
-        if ('data' in error && typeof error.data === 'string') {
-            return error.data;
+        if ('data' in error && error.data) {
+            if (typeof error.data === 'string') {
+                return error.data;
+            } else if (
+                typeof error.data === 'object' &&
+                'message' in error.data &&
+                typeof error.data.message === 'string'
+            ) {
+                return error.data.message;
+            }
         } else if ('statusText' in error && typeof error.statusText === 'string') {
             return error.statusText;
         } else if ('message' in error && typeof error.message === 'string') {