Topic

Security, Sandboxing & Same-origin

Origin model, SOP, CORP/CORS, CSP, iframes & sandbox flags, COOP/COEP, and process isolation.

securitycsporigin

HTML

sample

<iframe sandbox="allow-scripts"></iframe>

CSS

sample

iframe { border: 1px solid #1e293b; }

JavaScript

sample

console.log('Always validate postMessage origin!')

Visualizer

Security & Sandboxing

Sandbox flags and CSP tweaks.

Visualizer

Security & Sandboxing

Origin model, sandbox flags, and CSP. Toggle isolation controls.

live

Controls

allow-scriptsallow-same-originCSP

Visualization

Sandbox attribute

sandbox="allow-scripts "

Always validate postMessage origins and keep execution inside sandboxed iframes or workers.

Why this matters

Connect the dots between specs (HTML, CSS, WebIDL) and engine behaviors (parser, layout, GPU). Use the sandbox to reproduce each step with your own snippets.