Use HeaderSmith – cod3rjava to override outgoing request headers directly in Firefox.
Features: - Add multiple header rules (name/value) and enable/disable each rule - Optional URL regex filter to apply rules only to matching URLs - Rules are stored locally in the browser (storage.local)
Privacy: - No data is collected or transmitted off-device. - The add-on only modifies request headers for requests matching your configuration.
Notes: Some headers may be restricted by Firefox and cannot always be modified.
