diff --git a/packages/backend/src/server/activitypub.ts b/packages/backend/src/server/activitypub.ts
index da6a00e58..bbbc231b8 100644
--- a/packages/backend/src/server/activitypub.ts
+++ b/packages/backend/src/server/activitypub.ts
@@ -67,7 +67,7 @@ router.get('/notes/:note', async (ctx, next) => {
 
 	const note = await Notes.findOne({
 		id: ctx.params.note,
-		visibility: In(['public', 'home']),
+		visibility: In(['public' as const, 'home' as const]),
 		localOnly: false,
 	});
 
@@ -96,7 +96,7 @@ router.get('/notes/:note/activity', async ctx => {
 	const note = await Notes.findOne({
 		id: ctx.params.note,
 		userHost: null,
-		visibility: In(['public', 'home']),
+		visibility: In(['public' as const, 'home' as const]),
 		localOnly: false,
 	});