Pass UTM params through to dashboard sign-up

[goosewin]

Adds utm.js, which saves first-touch UTM params to the kernel_utm cookie and appends them to dashboard.onkernel.com links on click. Launch posts link straight to docs pages, so the params were lost before sign-up.

To test, open /browsers/code-mode-webmcp?utm_source=x&utm_medium=social&utm_campaign=code-mode and click Sign up: the params are on the URL. Without params, links are unchanged.

Pairs with the UTM passthrough in kernel/website, which writes the same cookie.

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Note

Low Risk
Client-side marketing attribution only; sets a first-party cookie and rewrites outbound dashboard URLs with no server or auth impact.

Overview
Adds utm.js to the Mintlify docs so launch traffic that lands on docs with UTM query params still reaches dashboard sign-up with attribution.

On load, the script captures first-touch utm_* values into the shared kernel_utm cookie (30-day, kernel.sh domain when applicable, host-only for local preview). It does not overwrite an existing cookie, matching the website behavior.

On click and middle-click (capture phase), it rewrites links to dashboard.onkernel.com to append stored UTMs when the destination URL does not already include utm_ params.

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[mintlify]

Preview deployment for your docs. Learn more about Mintlify Previews.

Project	Status	Preview	Updated
Kernel	🟢 Ready	View Preview	Oct 18, 2026, 8:20 PM

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[mintlify]

Preview deployment for your docs. Learn more about Mintlify Previews.

Project	Status	Preview	Updated
Kernel	🟡 Building	–	Oct 15, 2026, 6:02 AM

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[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

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[cursor]

Attribution cookie ignores tracking preferences

Medium Severity

kernel_utm is a 30-day attribution cookie written and later appended to dashboard links without checking Do Not Track or c15t marketing consent. conceptual.js already gates the dashboard attribution handoff on those signals, and the privacy policy says advertising and attribution cookies honor DNT.

Additional Locations (1)

• utm.js#L96-L99

 

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