Header Override: Modify HTTP Headers & Cookies

Header Override is an open-sourced header editor tool that modify request headers, response headers, request Cookie values, and response Set-Cookie values. Create rules from the extension popup, choose whether each rule affects outgoing requests or incoming responses, and scope each rule with Chrome's declarative URL filter syntax. Header Override can add request headers, add response headers, append request Cookie values, and add response Set-Cookie values with common cookie attributes such as Domain, Path, SameSite, lifetime, and Secure. Use profiles to keep separate rule sets for development, QA, demos, clients, or debugging sessions. Profiles can be activated from the popup, and selected profiles can be exported or imported as JSON when you need to move configurations between browsers or machines. Rules are saved locally in Chrome and applied automatically with Chrome's declarativeNetRequest API. Header Override does not use analytics, tracking, remote code, or external servers. Features: - Set or remove custom request headers. - Set or remove custom response headers. - Append request Cookie values. - Add or delete response Set-Cookie values. - Configure response cookie attributes, including Domain, Path, SameSite, lifetime, Max-Age, and Secure. - Scope rules to specific URLs or URL patterns. - Enable or disable individual rules. - Pause or resume all rules with the master toggle. - Group rules into local profiles. - Activate a profile for the current debugging workflow. - Import and export selected profile configurations as JSON. - Add optional comments to label or document each rule. - See the number of successfully applied rules in the extension badge. - Store rules locally with no analytics, tracking, remote code, or external servers. - Automatic dark or light mode