diff --git a/adm/style/event/acp_overall_footer_after.html b/adm/style/event/acp_overall_footer_after.html
new file mode 100644
index 0000000..9fdd075
--- /dev/null
+++ b/adm/style/event/acp_overall_footer_after.html
@@ -0,0 +1,16 @@
+{% if S_PWA_OPTIONS %}
+<script>
+	const input = document.getElementById('pwa_short_name');
+	const maxLength = 12;
+
+	input.addEventListener('input', () => {
+		// Use Array.from to count characters correctly
+		const inputChars = Array.from(input.value);
+
+		// If input exceeds maxLength, truncate it
+		if (inputChars.length > maxLength) {
+			input.value = inputChars.slice(0, maxLength).join('');
+		}
+	});
+</script>
+{% endif %}
diff --git a/event/listener.php b/event/listener.php
index 43e90a1..fe6b689 100644
--- a/event/listener.php
+++ b/event/listener.php
@@ -169,6 +169,8 @@ public function acp_pwa_options($event)
 			];
 
 			$event->update_subarray('display_vars', 'vars', phpbb_insert_config_array($event['display_vars']['vars'], $my_config_vars, ['before' => 'legend4']));
+
+			$this->template->assign_var('S_PWA_OPTIONS', true);
 		}
 	}
 
@@ -213,7 +215,7 @@ public function pwa_short_sitename($value, $key)
 	{
 		$placeholder = $this->trim_shortname($this->config['sitename']);
 
-		return '<input id="' . $key . '" type="text" size="40" maxlength="12" name="config[' . $key . ']" value="' . $value . '" placeholder="' . $placeholder . '">';
+		return '<input id="' . $key . '" type="text" size="40" maxlength="24" name="config[' . $key . ']" value="' . $value . '" placeholder="' . $placeholder . '">';
 	}
 
 	/**