Modify HTTP Headers

Set HTTP request headers with URL matching, profiles, and import/export.

* Set HTTP request headers using key-value pairs (overwrite if present, add if absent) * Each rule supports URL matching (with wildcards like *://api.example.com/*); leave empty to apply to all requests * Toggle switch for each rule; global master switch to pause all rules at once * Toolbar icon badge shows status: number = active rules count, OFF = master switch disabled, ERR = rule sync failed (error details shown in popup) * Multiple Profiles: Store different rule sets like "Development" and "Testing", switch with one click * Full management page: Search rules, reorder (move up/down), batch enable/disable/delete * Import / Export: JSON format for easy team sharing and migration * Bilingual interface: Initial language detected from browser (Chinese for Mainland China/Hong Kong/Macau/Taiwan, English otherwise); manually switchable in popup or management page (applies to popup/management/help pages) * Built-in help docs: Click ? in popup or "Help" in management page for module-based explanations and FAQs * Rules enabled without header name will show a red border warning