Header Modifier

Header Modifier lets you easily modify HTTP request headers or redirect requests based on the website you're visiting. It's designed for developers, QA engineers, and power users who need flexible request customization for API testing, authentication, debugging, or local development. Features - Modify, add, or override HTTP request headers - Redirect requests to different URLs - Apply rules globally or only on specific websites - Enable/disable the extension, individual rules, or specific headers without losing your configuration - Smart autocomplete for URL patterns, header names, and common values - Auto-fill rules from the current tab - Search and organize rules by page pattern - Import and export rule configurations as JSON - Instant rule updates when navigating between pages or tabs Perfect for API authentication, custom headers, user-agent overrides, local development, and debugging web applications.