Docs

DevHeader has four things worth understanding on their own: how rules are scoped to domains, how redirects rewrite URLs, how mocks fake a response, and how profiles keep separate rule sets apart.

New to mocking? Start with How to mock API responses in Chrome.

Domains
Scope rules to specific sites, and the one-time permission grant.
Redirects
Rewrite request URLs with find/replace, simple or regex.
Mocks
Return a canned response instead of hitting the real network. Includes a step-by-step guide to mocking API responses in Chrome.
Manage Profiles
Switch between isolated rule sets, and export/import them.