: Professionals use it to test for vulnerabilities like Cross-Site Scripting (XSS) , SQL Injection , and Insecure Direct Object References (IDOR) by injecting malicious payloads into request parameters.

: It serves as a visual tool for learning how client-server interactions work "under the hood". Modern Versions and Alternatives

: Developers use it to debug API calls and ensure that their server-side scripts correctly handle various types of input and header data.

The Firefox Developer Edition comes with a built-in feature called "Network Inspector" that allows you to inspect and modify HTTP requests.

You're looking for information on how to tamper with data in Firefox, specifically for testing or debugging purposes. Here are some methods and tools you can use:

is a Firefox extension (originally for older versions, now largely replaced by tools like Temper Data or built-in DevTools) used to intercept and modify HTTP/HTTPS requests—commonly for web security testing or debugging.