diff --git a/stack/input/dropdown/dropdown.class.php b/stack/input/dropdown/dropdown.class.php
index 016312a63ba..e1250780931 100644
--- a/stack/input/dropdown/dropdown.class.php
+++ b/stack/input/dropdown/dropdown.class.php
@@ -90,6 +90,12 @@ protected function internal_construct() {
                     } else {
                         $this->extraoptions[$opt] = $arg;
                     }
+                    // ISS1824 - The extraoptions we're testing against here are just hideanswer and
+                    // allowempty because dropdown does not override base class extraoptions like other
+                    // inputs. This is a bit of a landmine and we should consider a refactor longer term.
+                    // For minimal code change now, continue allows multiple options but doesn't trigger the fall through
+                    // to error in the switch below for hideanswer and allowempty.
+                    continue;
                 }
 
                 switch ($option) {
diff --git a/tests/input_checkbox_test.php b/tests/input_checkbox_test.php
index 6c5e4d7a98a..586f7c4d808 100644
--- a/tests/input_checkbox_test.php
+++ b/tests/input_checkbox_test.php
@@ -641,4 +641,11 @@ public function test_validate_student_response_with_allowempty_nocorrect(): void
         $this->assertEquals('', $state->errors);
         $this->assertEquals('A correct answer is: This input can be left blank.',
             $el->get_teacher_answer_display($state->contentsmodified, $state->contentsdisplayed));
-    }}
+    }
+
+    public function test_validate_extra_options_hideanswer(): void {
+        $el = stack_input_factory::make('checkbox', 'ans1', $this->make_ta(), null, ['options' => 'hideanswer'], false);
+        $el->validate_extra_options();
+        $this->assertEquals([], $el->get_errors());
+    }
+}
diff --git a/tests/input_dropdown_test.php b/tests/input_dropdown_test.php
index 5b91813dfc3..a6c15fcbaed 100644
--- a/tests/input_dropdown_test.php
+++ b/tests/input_dropdown_test.php
@@ -293,6 +293,8 @@ public function test_render_nonotanswered(): void {
     public function test_render_hidenonotanswered(): void {
 
         $el = $this->make_dropdown(['options' => 'hideanswer,nonotanswered']);
+        $el->validate_extra_options();
+        $this->assertEquals([], $el->get_errors());
         $el->adapt_to_model_answer($this->make_ta());
         $expected = '<select data-stack-input-type="dropdown" id="menustack1__ans1" class="select'
             . self::$moodleclass . ' menustack1__ans1" '
@@ -310,6 +312,12 @@ public function test_render_hidenonotanswered(): void {
                         ), 'stack1__ans1', false, null));
     }
 
+    public function test_validate_extra_options_hideanswer(): void {
+        $el = stack_input_factory::make('dropdown', 'ans1', $this->make_ta(), null, ['options' => 'hideanswer'], false);
+        $el->validate_extra_options();
+        $this->assertEquals([], $el->get_errors());
+    }
+
     public function test_render_latex(): void {
 
         $el = $this->make_dropdown(['options' => 'LaTeX']);