Vitest Browser Mode

Not part of recipe e2e. Vitest Browser Mode runs component tests inside a real browser via Vite. That is a different product surface from untestutils recipes (prepare → start → live URL).

Track	Runner	Target
Recipe e2e (primary)	Vitest Node + Playwright / Playwright Test	Live URL from leaseTarget / harness
Nuxt unit	environment: 'untestutils'	In-process Vue/Nuxt
Browser Mode (optional, later)	Vitest browser provider	In-Vite UI components

Nuxt unit in Browser Mode

When test.browser.enabled is on and environment: 'untestutils', setup uses runtime/browser-entry (not the Node DOM entry):

1. Sets __NUXT_VITEST_ENVIRONMENT_BROWSER_ENTRY__ so the Node entry skips
2. Calls setupWindow only if the env is not already prepared
3. Registers the same worker-aware boot path as Node (registerNuxtSetupEntry / appIsolation)

This matches the nuxt/test-utils#1821 browser-entry shape, with untestutils’ opt-in appIsolation: 'worker' (see Vitest — appIsolation) instead of always-memoize.

Default CI does not run a real @vitest/browser job — Browser Mode stays Experimental in the Support matrix until that job exists. Enable Browser Mode in a dedicated project when you need real Chromium; Nuxt helpers remain mock-friendly without it.

1.0 stance

• Classic Node + Playwright against a leased URL remains the primary e2e path.
• A dedicated Browser Mode package/helpers may appear after 1.0 if dogfood appears — it will not replace recipes.
• Do not mix Browser Mode config with the e2e untestutils() plugin in one project.

See Support matrix · Roadmap.