diff --git a/packages/hydrooj/package.json b/packages/hydrooj/package.json
index 5b80ac7a9..d88a01a8f 100644
--- a/packages/hydrooj/package.json
+++ b/packages/hydrooj/package.json
@@ -1,6 +1,6 @@
 {
     "name": "hydrooj",
-    "version": "4.9.1",
+    "version": "4.9.2",
     "bin": "bin/hydrooj.js",
     "main": "src/plugin-api",
     "module": "src/plugin-api",
diff --git a/packages/hydrooj/src/upgrade.ts b/packages/hydrooj/src/upgrade.ts
index 032aa8b10..1a62c94b3 100644
--- a/packages/hydrooj/src/upgrade.ts
+++ b/packages/hydrooj/src/upgrade.ts
@@ -551,6 +551,10 @@ const scripts: UpgradeScript[] = [
             await problem.edit(pdoc.domainId, pdoc.docId, { data: pdoc.data });
         });
     },
+    async function _77_78() {
+        await document.coll.updateMany({ docType: document.TYPE_DISCUSSION }, { $set: { hidden: false } });
+        return true;
+    },
 ];
 
 export default scripts;