Too much sun or a feeding gap

What's happening

New leaves bleaching to a pale, washed-out yellow on the window side points to too much direct sun scorching the tender variegated growth. Pale, weak new leaves with no recent feeding instead point to a nutrient shortfall, since young growth is the first to show a lack of food.

How to fix it

Move the plant out of any direct sun into the bright, indirect light dumb cane prefers. If feeding is overdue, start a balanced liquid fertilizer at half strength through the growing season. New leaves that emerge after the change should come in a healthy green with crisp variegation.

This is general guidance based on common symptoms; individual plants vary.