Implement and ship approved UX improvements for Firefox screen, window, and tab sharing. Build accessible, tested, and localizable browser UI in a large codebase; collaborate with UX and QA, support testing with web conferencing services, and contribute through public code review. The role requires production front-end experience with JavaScript, HTML, and CSS, automated UI testing, rapid onboarding to mature codebases, and effective asynchronous communication.
About the team and role
Mozilla's Web Conferencing team owns the media capture and sharing features that make Firefox work for video calls: screen, window, and tab capture, and the interface users interact with when they share content in Google Meet, Zoom, or Jitsi.
We're bringing a set of screensharing improvements to Firefox. The backend work is complete and the UX has been designed and approved. We're looking for a front-end engineer on a fixed-term contract to implement it and ship it.
What you'll do
- Implement approved UX designs for Firefox's screen, window, and tab sharing experience, and see them through to release
- Build browser UI that holds up in a large, widely used codebase: tested, accessible, and localizable
- Work with UX on the cases a design didn't anticipate, and with QA on validating the result
- Support partner testing against major web conferencing services
- Land your work in mozilla-central through public code review on Phabricator
What you'll bring
- 4+ years building production user interfaces with JavaScript, HTML, and CSS
- Experience implementing an approved design faithfully, plus the judgment to flag it when the design meets a case it didn't anticipate
- Ability to get productive quickly in a large, mature codebase you didn't write
- Experience writing automated tests for user interfaces
- Strong asynchronous written communication, since the team is distributed across timezones
- Comfort working in public, since Bugzilla and Phabricator are open
Bonus qualifications
- Prior contributions to Firefox or another open-source browser
- Familiarity with Firefox front-end architecture: browser/, custom elements, XUL, Fluent localization
- Experience with WebRTC or getDisplayMedia
- Accessibility experience with modal dialogs and list navigation
- Experience with Mozilla's test frameworks (browser-chrome, mochitest)
- Experience using AI tooling effectively in front-end development
- Open source environment experience
Hiring Ranges:
Canada Tier 1 Locations
$145,000—$170,800 CAD
Canada Tier 2 Locations
$154,000—$168,000 USD
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