This issue of TLDR Dev brings you an AI context webinar, tutorials on storing HTML in favicons and adding JSON-LD to personal sites, plus deep dives on agentic AI, new developer tools (Recall, Loupe), and simplified AI agent deployments with temporary Cloudflare accounts. It also covers software buy-vs-build economics, ClickHouse’s decade of growth, common CORS pitfalls, startup funding news, and tips for getting work approved without explicit yes.

The article examines how Zoom bypassed CORS with an image-based hack to trigger its localhost webserver, exposing a security flaw rooted in developers’ confusion over same-origin policy. It outlines a secure solution—using strict Access-Control-Allow-Origin headers and CSP for localhost—and calls for clearer CORS education.

The article breaks down 20 free or generous-tier APIs—from weather and country data to crypto prices and image services—each with example endpoints, sample responses, use cases, and key notes on authentication or limits. It’s a toolkit guide for quickly adding common features without building backends from scratch.

This page displays the fallback message shown when JavaScript is disabled on Google Maps. It states that with JavaScript off the page remains empty and prompts you to enable it to see the map.

Markdown emerged in 2004 as a simple and intuitive way to format text for the web, developed by John Gruber to address the complexities of HTML. Its ease of use and effectiveness quickly led to widespread adoption across various platforms, fundamentally changing how content is created and shared online.