Firefox

 Firefox  is a free, open source web browser made by Mozilla.

IndieWeb Add-ons

 * Omnibear is a Micropub client
 * ⬇️ Install Omnibear
 * Verify Me is an add-on that provides a visual indicator for confirmed rel-me links!
 * ⬇️ Install Verify Me

Search Mozilla’s Add-on Directory for more IndieWeb add-ons

Bugs

 * 1196151 indie-config does not work

Hello
Firefox Hello was a WebRTC based feature for doing browser to browser calls, audio, video or both, which you can setup with a hyperlink as part of an indieweb communication/contact page. It was removed in version 49.

Share
Firefox introduced a "Share" toolbar button in Firefox 23 to share the current page to a share provider of the user’s choice, including any Known site (on Withknown.com or your own server). It was removed in version 57.

Firefox OS
Firefox OS is an open source mobile operating system developed by Mozilla, based on Linux and the Gecko web rendering engine.

Persona
Persona was a single-sign-on (SSO) protocol, open source project, and fallback server developed by Mozilla.