Chapter 69: Subresource Integrity (SRI) & Referrer Policy

Referrer Policy Delivery: HTTP Header vs Meta Tag

**Part 14: Security & Best Practices** — Chapter 69: Subresource Integrity (SRI) & Referrer Policy

LEARNING OBJECTIVES ⌵
  • Deliver Referrer Policy via the Referrer-Policy HTTP response header.
  • Configure document-level policies using <meta name="referrer" content="...">.
  • Understand precedence rules when multiple delivery methods are defined.
  • Apply fallback cascades for legacy browser compatibility.
🎬 INTERACTIVE VISUAL PIPELINE Core Architecture Simulation
🌐
1. Input
Directives & Tags
⚙️
2. Parse
Tokenizer & AST
🌳
3. Layout
Box Model & Flow
🎨
4. Render
GPU Paint & Composite
PHASE 1: INPUT & DIRECTIVES
Browser receives declarative markup stream, parsing tag tokens and initializing component state.

💻 Interactive Code Playground

SYS: ACTIVE
HULL: 98%
CORE: STABLE
NET: ONLINE
HTML STARSHIP CODE TERMINAL playground.html
root@STARSHIP-ALPHA:~/web-core# READY FOR COMPILATION █
LIVE RENDER & DIAGNOSTICS CORE TEMP: 45°C
INSPECTING DOM: VALID
TAGS: SCANNING...
# Preferred: Server HTTP Response Header (Highest Security & Precedence)
Referrer-Policy: strict-origin-when-cross-origin

📌 Key Takeaways

  • The HTTP header Referrer-Policy takes precedence over HTML meta tags and covers initial page subresource requests before HTML parsing begins.
  • Use the HTML <meta name="referrer"> tag when you do not have direct access to server HTTP configuration.
  • --

❓ Knowledge Check

1. Which of the following is correct?

2. Which of the following is correct?