Fix default state for dialog checkbox

webpage/fullscreen.ts

@@ -59,7 +59,7 @@ class Fullscreen{
                 const checkbox = document.createElement('input');
                 div.appendChild(checkbox)
                 const label=document.createElement("span");
-                checkbox.value=array[2];
+                checkbox.checked=array[2];
                 label.textContent=array[1];
                 div.appendChild(label);
                 checkbox.addEventListener("change",array[3]);