Three distinct load-induced flakes in the mobile suite, all root-caused from real traces:
1. gestures-longpress "quick tap": longPress() drove page.mouse.down + Node-side
waitForTimeout(200) + page.mouse.up — three CDP round-trips. Under load the browser saw
the pointerup >500ms after pointerdown, firing the app's real long-press so the
ContextSheet opened on a quick tap. New quickTap() helper dispatches pointerdown/up
entirely in-browser on one clock, so the earlier-due pointerup always cancels the 500ms
timer first — immune to CDP latency.
2/3. upload-cancel-confirm and sheet-escape interacted with server-rendered controls before
Svelte hydrated them (caption fill lost -> cancel() navigates to /feed; custom role=radio
/ leave-button click no-ops). Wait for a post-hydration readiness signal (composer
auto-focus / real profile name) before the first interaction — the same barrier the
passing feed-based specs already have. (These are now belt-and-suspenders given ssr=false,
but keep the specs robust regardless of render mode.)
Verified: mobile 22/22, and 0/50 full-mobile runs under load (was ~3/95 pre-fix).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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