And that’s a friend worth keeping.
On macOS, you open Terminal and whisper:
open -n -a /Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome --args --user-data-dir="/tmp/chrome_dev_test" --disable-web-security On Windows, you summon the Command Prompt: chrome disable cors
It begins, as all great debugging sessions do, with a red error message in the console.
You’ve just built a beautiful, responsive front-end. The buttons shimmer. The fonts are perfect. You’re fetching data from a local API—maybe a JSON server, maybe a Python Flask backend running on port 5000, while your React app purrs along on port 3000. You click the button, expecting data. And that’s a friend worth keeping
You refresh your local app. The fetch works. The data flows. The red error vanishes. For five glorious minutes, you feel like a god who has bent the will of the browser to your own.
You mutter the incantation that has united developers across time zones: "I'll just disable CORS in Chrome." For the uninitiated, disabling CORS (Cross-Origin Resource Sharing) in Chrome is not a toggle in the settings menu. It’s a back-alley deal with the browser’s executable, a command-line flag that feels both powerful and deeply wrong. The buttons shimmer
chrome.exe --user-data-dir="C:/Chrome dev session" --disable-web-security When you hit enter, a new Chrome window appears—not your polished everyday Chrome, but a scarred, temporary doppelgänger. A yellow banner warns you: "You are using an unsupported command-line flag: --disable-web-security."