diff --git a/client/src/store/sagas/failure.ts b/client/src/store/sagas/failure.ts
index d37a20a..24e6fb5 100644
--- a/client/src/store/sagas/failure.ts
+++ b/client/src/store/sagas/failure.ts
@@ -3,8 +3,7 @@ import { put } from 'redux-saga/effects';
 import { logout } from '../actions/logout';
 
 export function* failuresSaga(action) {
-  const err = action.error;
-  if (err instanceof GiteaUnauthorizedError) {
+  if (action.error instanceof GiteaUnauthorizedError) {
     yield put(logout());
   }
 }
diff --git a/client/src/util/gitea.ts b/client/src/util/gitea.ts
index 8cfd785..faff29b 100644
--- a/client/src/util/gitea.ts
+++ b/client/src/util/gitea.ts
@@ -2,6 +2,7 @@
 export class GiteaUnauthorizedError extends Error {
   constructor(...args: any[]) {
     super(...args)
+    Object.setPrototypeOf(this, GiteaUnauthorizedError.prototype);
   }
 }