Component Testing in 2026, the Return of the Browser

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Component tests started in real browsers with Karma: high fidelity, but slow feedback and painful config. Jest + JSDOM made tests fast and easy, but emulation can miss rendering, layout, and browser APIs.

Playwright and Vitest Browser Mode bring back browser-first testing with headless speed, parallel runs, and traces. We’ll compare the approaches and share migration tips for legacy code.

This talk has been presented at React Advanced 2026, check out the latest edition of this React Conference.

Guy Nesher
Guy Nesher
Video transcription, chapters and summary will be available later.

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