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
Similar Jobs
An Hour Ago
Blockchain • eCommerce • Fintech • Payments • Software • Financial Services • Cryptocurrency
Graduate research co-op focused on building Customer World Models and proactive intelligence: designing representation learning, foundation-model, reinforcement learning, and agentic systems; running experiments, publishing, and deploying research into production to improve long-horizon decision-making and customer-facing automation.
Top Skills:
JaxPythonPyTorch
Blockchain • eCommerce • Fintech • Payments • Software • Financial Services • Cryptocurrency
Build infrastructure and tooling for AI evaluation, including distributed execution, task-set validation, graders, human-review calibration, statistical reporting, online feedback loops, and offline-to-online analysis. Partner with product, engineering, data, and ML teams to create reliable evaluation workflows that support faster, statistically sound AI product decisions.
Top Skills:
Artificial IntelligenceContinuous IntegrationLarge Language ModelsMachine Learning
An Hour Ago
Blockchain • eCommerce • Fintech • Payments • Software • Financial Services • Cryptocurrency
Graduate research interns will own end-to-end projects to build customer world models and proactive intelligence: developing representation learning, foundation model, RL/agentic methods, evaluation frameworks, and shipping research into production to improve customer decision-making.
Top Skills:
Deep LearningFoundation ModelsJaxOptimizationPythonPyTorchRepresentation Learning
What you need to know about the Charlotte Tech Scene
Ranked among the hottest tech cities in 2024 by CompTIA, Charlotte is quickly cementing its place as a major U.S. tech hub. Home to more than 90,000 tech workers, the city’s ecosystem is primed for continued growth, fueled by billions in annual funding from heavyweights like Microsoft and RevTech Labs, which has created thousands of fintech jobs and made the city a go-to for tech pros looking for their next big opportunity.
Key Facts About Charlotte Tech
- Number of Tech Workers: 90,859; 6.5% of overall workforce (2024 CompTIA survey)
- Major Tech Employers: Lowe’s, Bank of America, TIAA, Microsoft, Honeywell
- Key Industries: Fintech, artificial intelligence, cybersecurity, cloud computing, e-commerce
- Funding Landscape: $3.1 billion in venture capital funding in 2024 (CED)
- Notable Investors: Microsoft, Google, Falfurrias Management Partners, RevTech Labs Foundation
- Research Centers and Universities: University of North Carolina at Charlotte, Northeastern University, North Carolina Research Campus

