[Windows][Pets] Input region is offset; pet stays click-through after Windows reboots

Environment

• Codex Windows package: OpenAI.Codex 26.901.1978.0, x64.
• Two monitors; portrait secondary monitor to the left. Primary logical resolution 2048x1152.
• Pet window DPI 120 (125% scaling).

Reproduction and impact

The pet is visible on the primary monitor, but right-clicking or dragging its body activates the desktop/window underneath. Both built-in and custom pets are affected. This has persisted for several days, including after full Windows reboots.

Read-only native scan (2026-09-04, UTC+8)

The helper used per-monitor-DPI-aware-v2 coordinates, in physical pixels.

• Overlay bounds: (1378,0)-(2344,1440), unchanged during the scan.
• Visible pet center, indicated by the user's cursor: (1841,741). WindowFromPoint selected the desktop.
• All 289 probes within +/-64 pixels of this point missed the overlay.
• Full overlay grid: 2400 probes, 24-pixel spacing. Only 323 selected the overlay: a 19x17 rectangle at sampled x=1390..1822, y=12..396, in its upper-left area. These are sampled ranges, not exact boundaries.
• Direct WM_NCHITTEST returned HTCLIENT at all 2400 grid points, with no failures or timeouts.
• Window visible, enabled, topmost; extended style 0x00280088. WS_EX_TRANSPARENT was NOT set.
• GetLayeredWindowAttributes failed; its zero alpha output is not evidence of actual zero opacity. GetWindowRgn returned 0; this is not proof of an empty region.

Already tried

• Reset saved pet position: moved it to the primary monitor, but did not fix input.
• Switched to a built-in pet.
• Fully exited and reopened Codex using its original icon.
• Rebooted Windows multiple times over several days.
• A temporary launcher requested --force-device-scale-factor=1, without improvement. Acceptance of this argument was not independently verified, so scaling is not ruled out. Normal launch has since been restored.

Expected / interpretation

The visible pet should receive right-click and drag input. The scan shows a mismatch between the visible body and the OS-selected input area. The exact cause is unconfirmed; please investigate input-shape application, coordinate conversion, and layered-window hit testing.

Potentially related: #34227, #41596. This report adds a spatial WindowFromPoint map and a reproduction without WS_EX_TRANSPARENT.

No source file, test, or entry point is named. Start by locating the Windows pet-window creation and input-shape or hit-testing code, then reproduce the issue using the reported DPI, monitor layout, and WindowFromPoint scan. Done means the visible pet body receives right-click and drag input after normal launches and Windows reboots.