[TheOrcDev]

Owner, 2026-10-28: "I don't see it moving." That was true of #900, for two reasons:

1. The drift only ran in the focused window, so it froze whenever another app had focus.
2. 10 px over a minute, under the 82 to 92% coats, changed the coated pixels by 1 to 3 grey levels. That is invisible.

Change

• Tuned live with the owner watching in the dev app (hot reload). It now sways up to 120 px across and 84 px down along two sines (25 s and 33 s).
  • It moves every 50 ms, under 2 px a step.
  • The stills overhang the window by 128 px, so no edge shows.
  • Over 3 s, 90% of pixels now change by up to 11 grey levels and 99% by up to 20, against 3 and 5 before.
• When it moves: whenever the window is on screen, even beside a focused app. It pauses where it is, and resumes without a jump, while:
  • the window is minimised or hidden (main's window:visible);
  • a recording or livestream runs;
  • Reduce Motion is on.
• session:take-running is a new main-to-renderer event.
  • Main computes it in takeRunning() from its own capture state. A Clips-only ring is not a take, and neither is a lost socket.
  • Main sends it to every window, and a window that loads during a take is told on load.
  • The aux windows' preload allowlists add onTakeRunning.
• Design skill, glossary and docs/live-backgrounds.md are updated.

Gates

• Green:
  • typecheck;
  • lint;
  • Prettier on the changed files;
  • check:text-files;
  • the ChromeGround tests: no edge shows, steps under 2 px, each pause signal holds and resumes, cleanup;
  • takeRunning tests: takes, the Clips ring, a lost socket;
  • the preload API policy, renderer security policy and IPC contract tests.
• Not run: the full desktop suite and probe:ui-glass. The owner asked to merge.

Known issue, follow-up owed

• The drift sometimes pauses on its own shortly after launch.
  • Seen twice in a fresh profile: once while the owner looked, and once in the cost run, which went from moving to paused within 30 s.
  • A reload resumes it.
  • Ruled out: theme switches, hiding and showing the app, Reduce Motion, and Clips' starting status (already marked Clips-only).
  • Diagnosing next.
• Cost at this tuning is not re-measured, because the measurement hit the pause above. At the first tuning, drifting cost about 0.8% more of a GPU-process core and about 20 MB of GPU memory.

[coderabbitai]

Caution

Review failed

The pull request is closed.

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