diff --git a/app/components/Collaborators.tsx b/app/components/Collaborators.tsx
index 360e33ffd9..0f554e9b51 100644
--- a/app/components/Collaborators.tsx
+++ b/app/components/Collaborators.tsx
@@ -79,10 +79,10 @@ function Collaborators(props: Props) {
   // Memoize ids to avoid unnecessary effect executions
   const missingUserIds = useMemo(
     () =>
-      uniq([...document.collaboratorIds, ...Array.from(presentIds)])
+      uniq([...collaboratorIdsSet, ...presentIds])
         .filter((userId) => !users.get(userId))
         .sort(),
-    [document.collaboratorIds, presentIds, users]
+    [collaboratorIdsSet, presentIds, users]
   );
 
   useEffect(() => {
diff --git a/server/presenters/document.ts b/server/presenters/document.ts
index 7daf3e63e9..6f93f7fa42 100644
--- a/server/presenters/document.ts
+++ b/server/presenters/document.ts
@@ -109,7 +109,7 @@ async function presentDocument(
     res.parentDocumentId = document.parentDocumentId;
     res.createdBy = presentUser(document.createdBy);
     res.updatedBy = presentUser(document.updatedBy);
-    res.collaboratorIds = document.collaboratorIds;
+    res.collaboratorIds = document.collaboratorIds ?? [];
     res.templateId = document.templateId;
     res.insightsEnabled = document.insightsEnabled;
     res.popularityScore = document.popularityScore;