diff --git a/src/activitypub/mocks.js b/src/activitypub/mocks.js
index dbebb55693..660cb223f9 100644
--- a/src/activitypub/mocks.js
+++ b/src/activitypub/mocks.js
@@ -566,6 +566,7 @@ Mocks.actors.category = async (cid) => {
 		'@context': [
 			'https://www.w3.org/ns/activitystreams',
 			'https://w3id.org/security/v1',
+			'https://join-lemmy.org/context.json',
 		],
 		id: `${nconf.get('url')}/category/${cid}`,
 		url: `${nconf.get('url')}/category/${slug}`,