diff --git a/packages/firestore/src/local/simple_db.ts b/packages/firestore/src/local/simple_db.ts
index 322e0a6c384..38be5cb7cfd 100644
--- a/packages/firestore/src/local/simple_db.ts
+++ b/packages/firestore/src/local/simple_db.ts
@@ -209,7 +209,7 @@ export class SimpleDb {
   static isMockPersistence(): boolean {
     return (
       typeof process !== 'undefined' &&
-      process.env.USE_MOCK_PERSISTENCE === 'YES'
+      process.env?.USE_MOCK_PERSISTENCE === 'YES'
     );
   }
 
diff --git a/packages/firestore/test/util/test_platform.ts b/packages/firestore/test/util/test_platform.ts
index a1974fa4e25..3d09b59dd46 100644
--- a/packages/firestore/test/util/test_platform.ts
+++ b/packages/firestore/test/util/test_platform.ts
@@ -45,7 +45,8 @@ export class FakeWindow {
     });
     this.fakeIndexedDb =
       fakeIndexedDb ||
-      (typeof window !== 'undefined' && window.indexedDB) || null;
+      (typeof window !== 'undefined' && window.indexedDB) ||
+      null;
   }
 
   get localStorage(): Storage {