Test one web app as different devices, locales and networks at once
Short answerIn QA SessionLab every session can carry an environment preset: iPhone/Android/iPad/desktop viewport, offline/3G/4G throttling, locale and Accept-Language, timezone (including JavaScript Date math), dark mode, reduced motion and geolocation. Open the same page in several sessions to compare them.
Step by step
- Open a session’s detailsSide panel → Sessions → expand a session → Environment emulation.
- Pick the environmentChoose device, network, locale, timezone, colour scheme and geolocation.
- Open the pageThe preset applies to that session’s tabs and survives reloads and navigation.
- CompareUse the Role matrix to open the same URL in several differently-configured sessions.
Why this works
- Timezone, locale and slow-network bugs rarely show on a developer’s machine.
- Per-session presets let you keep one “Jakarta, Bahasa, 3G” user next to a “New York, English, desktop” user.
Questions
Why does Chrome show “started debugging”?
Device size, network throttling and colour scheme use Chrome’s debugger API, which always shows that bar. Locale, timezone and geolocation are emulated in-page without it.