What to inspect
Check whether leaves touch glass, the overnight minimum near the plant, draft paths, moisture, and the boundary between firm and soft tissue.
Choose one evidence-based action
Move the plant away from cold contact, keep conditions stable, and avoid watering merely because damage looks dry later.
What not to do
Do not diagnose cold-window damage from one mark, change several major conditions at once, or use an unlabeled treatment. Old damage may remain after the cause is corrected.
Review the outcome
Photograph the same area under similar light, record the date and intervention, then compare the boundary of damage and the quality of new growth. Escalate rapid decline or safety concerns to an appropriate professional.