Inject HTMLfiles into htmlfiles including nested templates, then load Dom-dependant Javascript files.
Add to HTML via Include Tags like in this example...
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Include HTML Sample</title>
<script src="./js/incudeHTML.js" defer></script>
</head>
<body>
<div class="flexBack" style="display: flex; height: 100vh;">
<contents>
<include DS-Template="./Header.html"></include>
<main-db>
<include DS-Template="./SideBarL.html"></include>
<include DS-Template="./Form.html"></include>
<include DS-Template="./SideBarR.html"></include>
</main-db>
<include DS-Template="./Footer.html"></include>
</contents>
</div>
</body>
</html>