diff --git a/webapp/src/Controller/API/ClarificationController.php b/webapp/src/Controller/API/ClarificationController.php
index 81f1a560ca..397e2e499b 100644
--- a/webapp/src/Controller/API/ClarificationController.php
+++ b/webapp/src/Controller/API/ClarificationController.php
@@ -277,8 +277,10 @@ protected function getQueryBuilder(Request $request): QueryBuilder
             ->leftJoin('clar.sender', 's')
             ->leftJoin('clar.recipient', 'r')
             ->leftJoin('clar.problem', 'p')
+            ->innerJoin('c.problems', 'cp')
             ->select('clar, c, r, reply, p')
             ->andWhere('clar.contest = :cid')
+            ->andWhere('clar.problem IS NULL OR clar.problem = cp.problem')
             ->setParameter('cid', $this->getContestId($request))
             ->orderBy('clar.clarid');
 
diff --git a/webapp/src/Controller/Jury/ClarificationController.php b/webapp/src/Controller/Jury/ClarificationController.php
index 4c8a6f8fa1..4eda5224e2 100644
--- a/webapp/src/Controller/Jury/ClarificationController.php
+++ b/webapp/src/Controller/Jury/ClarificationController.php
@@ -193,7 +193,12 @@ public function viewAction(Request $request, int $id): Response
             $clarcontest = $contest->getShortname();
             $data['subjectlink'] = null;
             if ($clar->getProblem()) {
-                $concernssubject = $contest->getCid() . "-" . $clar->getProblem()->getProbid();
+                if ($clar->getContestProblem()) {
+                    $concernssubject = $contest->getCid() . "-" . $clar->getProblem()->getProbid();
+                } else {
+                    // Very special case, this problem is unlinked.
+                    $concernssubject = "";
+                }
                 $data['subjectlink'] = $this->generateUrl('jury_problem', ['probId' => $clar->getProblem()->getProbid()]);
             } elseif ($clar->getCategory()) {
                 $concernssubject = $contest->getCid() . "-" . $clar->getCategory();
diff --git a/webapp/src/Twig/TwigExtension.php b/webapp/src/Twig/TwigExtension.php
index c1309fe6b7..60df1de6cc 100644
--- a/webapp/src/Twig/TwigExtension.php
+++ b/webapp/src/Twig/TwigExtension.php
@@ -1179,9 +1179,9 @@ public function fileTypeIcon(string $type): string
         return 'fas fa-file-' . $iconName;
     }
 
-    public function problemBadge(ContestProblem $problem, bool $grayedOut = false): string
+    public function problemBadge(?ContestProblem $problem, bool $grayedOut = false): string
     {
-        $rgb = Utils::convertToHex($problem->getColor() ?? '#ffffff');
+        $rgb = Utils::convertToHex($problem?->getColor() ?? '#ffffff');
         if ($grayedOut || empty($rgb)) {
             $rgb = Utils::convertToHex('whitesmoke');
         }
@@ -1197,7 +1197,7 @@ public function problemBadge(ContestProblem $problem, bool $grayedOut = false):
             $rgb,
             $border,
             $foreground,
-            $problem->getShortname()
+            $problem?->getShortname() ?? '?'
         );
     }