diff --git a/src/Handler/Course.hs b/src/Handler/Course.hs
index a23709849..1f3ee0117 100644
--- a/src/Handler/Course.hs
+++ b/src/Handler/Course.hs
@@ -36,33 +36,30 @@ postCNotesR _ _ _ = defaultLayout [whamlet|You have corrector access to this cou
 
 postCFavouriteR :: TermId -> SchoolId -> CourseShorthand -> Handler ()
 postCFavouriteR tid ssh csh = void $ do
-  muid <- maybeAuthPair
+  authPair@(uid, _) <- requireAuthPair
   runDB $ void $ do
-    mcid <- getKeyBy404 $ TermSchoolCourseShort tid ssh csh
-    if | Just cid <- mcid, Just uid <- view _1 <$> muid -> do
-          now <- liftIO getCurrentTime
-          -- Nothing means blacklist
-          -- should never return FavouriteCurrent
-          newReason <- storedFavouriteReason tid ssh csh muid <&> (\case
-            -- Maybe (Maybe reason, blacklist)
-            Nothing                             -> Just FavouriteManual
-            Just (_reason, True)                -> Just FavouriteVisited
-            Just (Just FavouriteManual, False)  -> Nothing
-            Just (_reason, False)               -> Just FavouriteManual)
-          -- change stored reason in DB
-          case newReason of
-            (Just reason) -> do
-              void $ E.upsertBy
-                (UniqueCourseFavourite uid cid)
-                (CourseFavourite uid cid reason now)
-                [P.Update CourseFavouriteReason reason P.Assign]
-              E.deleteBy $ UniqueCourseNoFavourite uid cid
-            Nothing -> do
-              E.deleteBy $ UniqueCourseFavourite uid cid
-              void $ E.upsertBy
-                (UniqueCourseNoFavourite uid cid)
-                (CourseNoFavourite uid cid)
-                []  -- entry shouldn't exists, but keep it unchanged anyway
-       | otherwise -> pure ()
+    cid <- getKeyBy404 $ TermSchoolCourseShort tid ssh csh
+    now <- liftIO getCurrentTime
+    -- should never return FavouriteCurrent
+    newReason <- storedFavouriteReason tid ssh csh (Just authPair) <&> (\case
+      -- Maybe (Maybe reason, blacklist)
+      Nothing                             -> Just FavouriteManual
+      Just (_reason, True)                -> Just FavouriteVisited
+      Just (Just FavouriteManual, False)  -> Nothing
+      Just (_reason, False)               -> Just FavouriteManual)
+    -- change stored reason in DB
+    case newReason of
+      (Just reason) -> do
+        void $ E.upsertBy
+          (UniqueCourseFavourite uid cid)
+          (CourseFavourite uid cid reason now)
+          [P.Update CourseFavouriteReason reason P.Assign]
+        E.deleteBy $ UniqueCourseNoFavourite uid cid
+      Nothing -> do
+        E.deleteBy $ UniqueCourseFavourite uid cid
+        void $ E.upsertBy
+          (UniqueCourseNoFavourite uid cid)
+          (CourseNoFavourite uid cid)
+          []  -- entry shouldn't exists, but keep it unchanged anyway
   -- show course page again
   redirect $ CourseR tid ssh csh CShowR