Header Modifier

修改 Web 请求的 Headers，支持新增自定义 key/value

Header Modifier lets you rewrite HTTP headers on the requests your browser makes. It is built for developers who need to test an API against a staging gateway, pass a debug flag, override a User-Agent, or strip a header to reproduce a bug. FEATURES • Simple by default — type a header name and value, and it applies to every request. Advanced options stay folded away until you need them. • Per-rule URL matching — each rule has its own pattern, so one rule can target your staging API while another targets a CDN. One click fills in the current site. • Request and response headers — modify either direction. • Three operations — Set to overwrite, Append to add to an existing value, Remove to strip a header entirely. • Per-rule toggles plus a master switch — pause everything with one click without losing your rules. • Live rule count in the toolbar badge, so you always know what is active. HOW IT WORKS Click the toolbar icon, hit "Add header", and type the header name and value. That is the whole flow — the rule applies to all URLs immediately. Need something narrower? Expand the row to set a URL pattern, switch to response headers, or change the operation. The collapsed summary always tells you what a rule does, so you can scan a long list at a glance. URL patterns follow Chrome's urlFilter syntax, for example: *://api.example.com/* only that host *staging* any URL containing "staging" PRIVACY Header Modifier collects nothing. There is no analytics, no telemetry, and no remote server. Your rules are stored locally with chrome.storage.local and never leave your machine. The extension uses Chrome's declarativeNetRequest API, which is declarative by design: the extension gives Chrome a list of rules and Chrome enforces them. The extension never observes your traffic and cannot read page content or request bodies. NOTES • Append is only honoured on response headers and a small set of request headers (cookie, accept, accept-encoding, accept-language, user-agent). For other request headers, use Set. The popup warns you when this applies. • Chrome does not allow modifying some security-critical headers. If Chrome rejects a rule, the popup shows the reason. • Open source: https://github.com/Vizards8/chrome-header-modifier