How does the browser get into the right account?
Website authentication crosses several boundaries: the user who authorizes access, the system that holds credentials, the browser that submits them, and any model or code driving the page. Reusing a login and collecting a new identity are separate workflows.
For a customer-facing app, associate each stored connection with the correct application user before opening a browser. Reusing another user's profile can produce a technically successful run in the wrong account.
Compare the login path
Kernel: Managed Auth handles website login and eligible connection recovery. Vault fill is a separate flow for applications that control navigation and form submission; the reviewed vault documentation labels that surface as preview.
Browser Use: V4 secret bindings give credentials aliases and allowed hostnames for use in a run. Profiles reuse existing state; the separate 2FA guide addresses verification during authenticated work.
Compare saved state
Kernel: Profiles preserve browser user-data-directory state, including cookies, site data, tabs and preferences. Profile sharing and save behavior need explicit treatment when parallel workers use seeded state.
Browser Use: Profiles persist cookies, local storage and login state between browsers. Browser settings select a profile for a run. A session's conversation history and a profile's browser state are different resources.
Compare the evidence from a run
Kernel: Live browser URLs support an embedded view and a read-only option. Replays and browser telemetry are separate observability surfaces; app invocation logs add execution context.
Browser Use: Browser Use documents live preview and recording. Recording availability follows the browser lifecycle and processing state; a live URL is for an active browser rather than a permanent replay link.
How to evaluate this choice
Compare the concrete login path. A vault can fill a secret while your code controls the workflow; a managed connection may own more of the login process. Neither should be described as a universal guarantee that every website remains signed in.
- Identify whether the task uses an existing account or creates an approved new identity.
- Separate profile restoration from credential fill and connection readiness.
- Document which component can access credential values and which only handles references.
- Verify the expected tenant and account after login.
- Provide a human handoff when the website requires user interaction.
Requirements side by side
| Requirement | Kernel | Browser Use |
|---|---|---|
| Saved browser state | Documented | Documented |
| Credential handling | Vaults (preview) | V4 secret bindings |
| Website sign-in | Documented | Profile / 2FA flows |
Sources: kernel.sh [1] ↗kernel.sh [2] ↗kernel.sh [3] ↗kernel.sh [4] ↗kernel.sh [5] ↗kernel.sh [6] ↗docs.browser-use.com [7] ↗docs.browser-use.com [8] ↗docs.browser-use.com [9] ↗docs.browser-use.com [10] ↗
Which approach fits?
Choose Kernel when your code makes many browser calls and you want to deploy it beside the browser, or you need Kernel's managed sign-in flow.
Kernel tradeoff: Browser-local code changes the deployment model. Check app action behavior, account limits and persistent-state ownership before moving an external worker into it.
Choose Browser Use when you use Browser Use's framework or want its hosted browsers while retaining the option of a hosted browser agent.
Browser Use tradeoff: A hosted-agent run is a different execution unit from your deployed browser script. Keep comparisons focused on the browser path when measuring session speed and price.
A useful acceptance check
Write a pass/fail result for the real task before running the evaluation. Record the account, configuration and code version next to that result. Repeat failures need an explanation, not an automatically different browser configuration.
When Notte belongs on this shortlist
Kernel's browser-local Apps make execution placement part of the decision. Compare the repeated action path with the proposed Notte controller or Function deployment before concluding that a lifecycle or hourly-rate difference decides the workflow.
Browser Use's hosted-agent offering and standalone browser infrastructure are separate options. Keep the comparison at the browser layer when your application already owns its controller; compare execution ownership separately if the hosted agent is part of the requirement.
Notte: Vaults substitute credential placeholders in supported browser actions outside the model context. Managed Auth checks requested saved connections before automation. Personas supply an inbox and optional phone number for verification workflows.
Consider this third option when its documented mechanism addresses a requirement left open by the two providers above. A working configuration on either original provider can still be the better choice; compare the task and ownership cost before switching.
Sources: kernel.sh [1] ↗docs.browser-use.com [2] ↗docs.notte.cc [3] ↗