Start analytics on mount, because a prerendered page never re-runs load - #162
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The previous commit put `initAnalytics()` in the root `+layout.ts` `load`, which is where PostHog's SvelteKit guide puts it. That guide assumes a page rendered per request. Every page here is prerendered by adapter-static, and SvelteKit hydrates a prerendered page from the serialised layout data instead of re-running the universal `load` — so `load` fired on an internal client-side navigation and never on a visit arriving from outside, which is most of them. It looked fine locally because `vite preview` reached it through a navigation. On langx.io the deployed bundle carried the key and the whole config and the PostHog chunk was still never fetched: no page view was ever counted. `onMount` runs on hydration, always. Verified the way it should have been the first time — against the built, prerendered output served as static files, entered cold from outside: the chunk is fetched, events reach eu.i.posthog.com/e/, and cookies, localStorage and sessionStorage all stay empty. That same measurement corrects section 3.4 of the cookie policy. It said the SDK also fetches a configuration file from PostHog's asset host, which is what `vite preview` showed; the real build makes no asset-CDN and no /flags request at all. The section now names the one connection that does happen rather than one that does not, and the note in analytics.ts says to re-measure request counts on a real build rather than trust a dev server. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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Follow-up to #161, which shipped analytics that never ran.
The bug
initAnalytics()went in the root+layout.tsload, which is where PostHog's SvelteKit guide puts it. That guide assumes a page rendered per request. Every page here is prerendered byadapter-static, and SvelteKit hydrates a prerendered page from the serialised layout data rather than re-running the universalload. Soloadfired on an internal client-side navigation and never on a visit arriving from outside — which is most of them.It looked fine in local testing because
vite previewreached it through a navigation. On langx.io the deployed bundle carried the key and the whole config, and the PostHog chunk was still never fetched. Not a single page view was counted.onMountruns on hydration, always.Verified properly this time
Against the built, prerendered output served as static files and entered cold from outside — the shape that actually ships, not a dev server:
eu.i.posthog.com/e/(The initial
$pageviewis batched — it flushes on a later capture or on page hide, so it does not appear in the network log in the first few seconds. That is PostHog's normal behaviour, not a second bug.)It also corrects the cookie policy
Section 3.4 said the SDK fetches a small configuration file from PostHog's asset host. That is what
vite previewshowed; the real build makes no asset-CDN request and no/flagscall. The section now names the one connection that does happen — page views to PostHog's EU endpoint — rather than one that does not. The note inanalytics.tssays to re-measure request counts on a real build rather than trust a dev server.Separately, and not fixed here
static.cloudflareinsights.comis loading on langx.io — Cloudflare Web Analytics, injected by Cloudflare Pages, not by this repo. It predates these PRs, but cookie policy §3.4 currently implies nothing third-party is measuring the site. It is either worth turning off in the Cloudflare dashboard or worth naming in §3.4; that is a decision rather than a fix, so it is not in this PR.🤖 Generated with Claude Code