diff --git a/lib/config.ts b/lib/config.ts
index 3194943..1887442 100644
--- a/lib/config.ts
+++ b/lib/config.ts
@@ -46,6 +46,7 @@ export const VALID_CONFIG_KEYS = new Set([
     // Top-level keys
     'enabled',
     'debug',
+    'showUpdateToasts', // Deprecated but kept for backwards compatibility
     'pruningSummary',
     'strategies',
     // strategies.deduplication