Persona – Device Identity Switcher

Device identity switcher: User-Agent, Client Hints and JavaScript stay consistent with the device you pick. Built-in leak scorecard.

Modern websites look at much more than the User-Agent header: Client Hints (sec-ch-ua*), navigator.userAgentData, navigator.platform, touch points, screen size, device pixel ratio and pointer media queries. Change the header alone and the page still knows you are on a desktop. Persona switches the whole identity at once, so every layer tells the same story. WHAT IT DOES • 44 ready-made devices covering popular phones and tablets, desktop browsers on every major operating system, search-engine crawlers, the link-preview bots used by social networks and messaging apps, and AI crawlers. • One tap applies a device to the current tab. Pin it to a whole site or make it your default everywhere with one more tap. • Add your own device: paste any User-Agent string and Persona fills in the matching platform, Client Hints, touch and screen values. Everything stays editable. Duplicate a preset to start from something close. Import / export devices as JSON. • Consistency scorecard: shows what a website actually receives on every layer — request headers, Client Hints, JavaScript and Web Workers — and highlights each place where your real identity leaks through. • Per-tab badge on the toolbar icon so you always know which identity a tab is using. • Keyboard shortcut (Alt+Shift+U) opens the dashboard. WHO IT IS FOR • Web developers testing responsive layouts and device-specific code paths without a device lab. • SEO specialists viewing a page as Googlebot or as a social network's link-preview bot. • QA engineers reproducing browser-specific bugs. • Anyone checking how a site treats AI crawlers. HOW IT WORKS Persona uses Chrome's declarativeNetRequest API to rewrite the User-Agent, Accept-Language and sec-ch-ua* request headers, and injects a small script at document start that makes navigator, userAgentData, screen and pointer media queries report the same device. Rules are evaluated per tab, so different tabs can be different devices at the same time. PRIVACY Persona has no server, no analytics and no accounts. Your settings stay in Chrome's extension storage. The only network request the extension itself makes is the optional header check in the scorecard, which you trigger manually and whose endpoint you can change. Full policy: https://manhdev.click/projects/persona/privacy KNOWN LIMITS • Web Workers and Service Workers keep the real navigator.userAgent (content scripts cannot reach them). The scorecard tells you when that matters. • Pages Chrome protects (chrome://, the Web Store) only receive header changes. Website: https://manhdev.click/projects/persona