grafana/k6 · error

enabling page lifecycle events: %w

Error message

enabling page lifecycle events: %w

What it means

FrameSession.initIsolatedWorld (frame_session.go:456) begins by sending Page.setLifecycleEventsEnabled(true) so k6 can observe load/domContentLoaded/networkIdle. If the CDP command fails, world initialization aborts with this wrapped error. Failures here are environmental: the target is gone or the CDP session is broken, since this command has no script-controllable parameters.

Source

Thrown at internal/js/modules/k6/browser/common/frame_session.go:456

		return fmt.Errorf("got a nil page frame tree")
	}

	// Any new frame may have a child frame, not just mainframes.
	fs.handleFrameTree(frameTree, fs.isMainFrame())

	if fs.isMainFrame() {
		fs.initRendererEvents()
	}
	return nil
}

func (fs *FrameSession) initIsolatedWorld(name string) error {
	fs.logger.Debugf("NewFrameSession:initIsolatedWorld",
		"sid:%v tid:%v", fs.session.ID(), fs.targetID)

	action := cdppage.SetLifecycleEventsEnabled(true)
	if err := action.Do(cdp.WithExecutor(fs.ctx, fs.session)); err != nil {
		return fmt.Errorf("enabling page lifecycle events: %w", err)
	}

	if _, ok := fs.isolatedWorlds[name]; ok {
		fs.logger.Debugf("NewFrameSession:initIsolatedWorld",
			"sid:%v tid:%v, not found: %q",
			fs.session.ID(), fs.targetID, name)

		return nil
	}
	fs.isolatedWorlds[name] = true

	var frames []*Frame
	if fs.isMainFrame() {
		frames = fs.manager.Frames()
	} else {
		frame, ok := fs.manager.getFrameByID(cdp.FrameID(fs.targetID))
		if ok {
			frames = []*Frame{frame}

View on GitHub (pinned to 93accf6570)

Solutions

1. Perform waits against a stable, fully loaded page (chain after goto with a suitable waitUntil)
2. Ensure pages are not closed by the application while k6 is setting up waits
3. Reduce per-renderer memory pressure (fewer VUs/pages) if renderer crashes are the root cause

try {
  frame.waitForSelector(sel);
} catch (e) {
  if (/enabling page lifecycle events/i.test(String(e))) {
    // target invalidated between world creation and this CDP call — re-run after page settles
  }
}

When it happens

Trigger: The first waitForSelector/waitForFunction call triggers isolated-world setup; if the page has navigated away, crashed, or been closed in the meantime, this command fails. Also seen when the renderer dies under memory pressure.

Common situations: Calling waitFor* immediately after a navigation that invalidates the context, page closed by site JS (window.close), chromium renderer OOM crashes in long test runs.

Related errors

• adding script to evaluate on new document: %w
• adding k6 object to new browser context: %w
• getting page frame tree: %w
• WebSocket endpoint cannot be empty
• can't fetch the page for unknown reason

AI-assisted analysis of grafana/k6@93accf6570 (2026-08-15). Data as JSON: /api/errors/063039728b5fde10. Report an issue: GitHub.