Demo : https://e-caliskan.github.io/pdf-page-merger-editor/

It is a very lightweight and useful tool that uses html, javascript and css to merge, delete, rotate and change the order of pages of the PDF files you add.

Affected libraries;

https://cdnjs.cloudflare.com/ajax/libs/pdf-lib/1.17.1/pdf-lib.min.js

https://cdnjs.cloudflare.com/ajax/libs/pdf.js/2.9.359/pdf.min.js

https://cdn.jsdelivr.net/npm/[email protected]/Sortable.min.js

https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.15.3/css/all.min.css