diff --git a/packages/hydrooj/src/upgrade.ts b/packages/hydrooj/src/upgrade.ts
index c88551eb9..303dfef41 100644
--- a/packages/hydrooj/src/upgrade.ts
+++ b/packages/hydrooj/src/upgrade.ts
@@ -678,7 +678,7 @@ export const coreScripts: MigrationScript[] = [
             const wanted = handleMailLower(udoc.mail);
             if (wanted !== udoc.mailLower) {
                 if (await user.getByEmail('system', wanted)) {
-                    console.warn('Email conflict: %s', wanted);
+                    console.warn('Email conflict when trying to rename %s to %s', udoc.mailLower, wanted);
                     return;
                 }
                 await user.coll.updateOne({ _id: udoc._id }, { $set: { mailLower: wanted } });
diff --git a/packages/ui-default/pages/contest_scoreboard.page.ts b/packages/ui-default/pages/contest_scoreboard.page.ts
index e8d1160eb..383286868 100644
--- a/packages/ui-default/pages/contest_scoreboard.page.ts
+++ b/packages/ui-default/pages/contest_scoreboard.page.ts
@@ -7,7 +7,7 @@ const page = new NamedPage(['contest_scoreboard', 'homework_scoreboard'], async
   const db = await openDB;
   const { tdoc } = UiContext;
   const id = `${tdoc.domainId}/${tdoc.docId}`;
-  const read = async () => (await db.get('scoreboard-star', id)).value || [];
+  const read = async () => (await db.get('scoreboard-star', id))?.value || [];
   const write = (data) => db.put('scoreboard-star', { id, data });
 
   $(`.star.user--${UserContext._id}`).closest('tr').addClass('star-highlight');