javascript : how to display and scroll a remote pdf, on a browser non dependant way

You can load and display a remote PDF in a fully browser-independent way using pdf.js,
No need using iframe/embed/object. pdf.js can fetch a PDF directly from a URL as long as the server allows CORS.
Below is a minimal working example that loads a remote PDF, renders every page into a <canvas>, and lets you control scrolling yourself.

html & js

<div id="pdf-container" style="height:600px; overflow-y:auto;"></div> <script src="https://cdnjs.cloudflare.com/ajax/libs/pdf.js/4.0.379/pdf.min.js"></script> pdfjsLib.GlobalWorkerOptions.workerSrc = "https://cdnjs.cloudflare.com/ajax/libs/pdf.js/4.0.379/pdf.worker.min.js"; const url = "https://example.com/your.pdf"; // remote PDF URL pdfjsLib.getDocument(url).promise.then(pdf => { for (let i = 1; i <= pdf.numPages; i++) { pdf.getPage(i).then(page => { const viewport = page.getViewport({ scale: 1.2 }); const canvas = document.createElement("canvas"); const ctx = canvas.getContext("2d"); canvas.height = viewport.height; canvas.width = viewport.width; document.getElementById("pdf-container").appendChild(canvas); page.render({ canvasContext: ctx, viewport: viewport }); }); } });

The only requirement is that the server hosting the PDF must send the proper CORS header,
here is like example:

Access-Control-Allow-Origin: *

Then that header is in place, pdf.js can fetch and render the PDF .

Slightly unclear but a PDF is a vector file of pages thus cannot be shown normally in a browser.

Hence the need for

An embedded frame with scrollbars controlled by a client only (Chromium's FireFox Gecko's based PDF viewers etc.) Alternative is something like PDF.JS which is an images renderer with overlays and scrollbars. A remaining possibility is (if browsers ALLOW images, not all do) then place canvas images side by side or one over the other and then the page scrolls not the images.