Firefox use WebExtensions, but its native messaging registration differ from Chromium. Flux get a dedicated Gecko identity and host manifest, while the desktop transfer protocol remain the same. Correct package, permission, host connection and signing condition all matter for a reliable setup.
Choose the Firefox package
Use the Firefox extension wey match the desktop release. Its manifest carry a Gecko extension ID. Renaming a Chromium archive no turn am into a valid Firefox package. Follow version-specific installation instructions.
Understand signing
Normal Firefox releases need Mozilla signing for permanent installation. Temporary developer loads fit disappear after browser restart. Host registry repair no change that rule. Check current release notes instead of assuming every archive get store approval.
Register the desktop bridge
Launch Flux once and allow startup check host registration. Repair Browser integration in Settings if necessary. Firefox manifest use allowed_extensions; Chromium use allowed_origins. The desktop manage these registrations separately.
Test the complete route
Grant permissions, refresh the tab and inspect a supported video. Confirm the desktop receive the selected format. If e fail, keep the error, browser version and package version. Remove private session data before reporting the problem.
Sources and release details
This guide follow Flux 2.6.6 documents. Check the current release record for the conditions wey follow each package.
