Problem

Dashboards do not have a compact first-party way to show what is happening right now. This product experiment adds a narrowly scoped live activity tile inspired by PostHog#62806 without introducing a separate analytics engine.

Changes

• Adds a live_activity dashboard widget type to the backend registry, catalog, default layout, generated config schemas, frontend registry, and MCP generated surfaces.
• Runs bounded HogQL queries for a fixed 5-minute rolling window: active distinct IDs, a 20-bucket activity pulse, and a short recent-events feed capped at 10 rows.
• Labels web, mobile, and backend activity from event name, $lib, and target properties without per-row person lookups.
• Adds a WidgetCard UI with loading, empty, delayed, error-through-card-shell, permissions-through-registry, pause/resume, manual refresh, hidden-tab auto-pause, narrow layout, edit modal, story fixtures, and preview states.
• Keeps the generated config contract as the source of truth and adds coverage for widget registry/config/query/layout behavior.

How did you test this code?

As an agent, I ran:

• hogli build:openapi && hogli build:widget-types
• hogli test products/dashboards/backend/api/test/test_run_widgets.py products/dashboards/backend/api/test/test_dashboard_widgets.py products/dashboards/backend/api/test/test_widget_config_schema_parity.py products/dashboards/backend/test/test_widget_layouts.py products/dashboards/backend/widgets/test/test_live_activity_widget.py — 148 passed
• Frontend widget Jest suite — 41 passed
• pnpm --filter=@posthog/frontend typescript:check
• MCP typecheck/vitest for generated dashboard tool schemas — 1829 tests passed
• Query sanity through the live widget runner with CLICKHOUSE_DATABASE=posthog: 3.35s locally, 4 active users, 5 events in window, seeded web/mobile/backend events visible
• Running-app verification on a seeded dashboard: live events rendered, pause produced 0 scheduled run_widgets requests over 17s, simulated document.hidden=true produced 0 scheduled requests over 17s, and resume/manual refresh picked up delayed events

Automatic notifications

• Publish to changelog?
• Alert Sales and Marketing teams?

Docs update

No docs update for this experiment PR. The widget copy documents the fixed 5-minute window and hidden-tab pause behavior inline.

🤖 Agent context

Autonomy: Human-driven (agent-assisted)

Captain Capy implemented this PR from a human request, using the dashboard-widget management workflow and generated API/type tooling. Two deterministic visual directions were explored before implementation; the selected direction keeps the tile compact, uses existing dashboard widget/query infrastructure, and avoids high-frequency polling, unbounded payloads, and per-row requests.

The hidden-tab behavior was verified by simulating document.hidden=true in Playwright because headed/headless browser tabs remained visible in this environment.

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