How to reduce the number of empty color wells in macOS Colors window

The space at the bottom of the Colors window has grown to include hundreds of empty color wells. (image -1) This growth even survived a transition to macOS Sonoma.

I can move either side over so it shows just ten wells per row (image -2), but I haven't figured out a way to shrink the number of rows. Sliding up the bottom of the window only cuts off the color choices above the lower section of the window (image -3).

iMac Apple M3 running macOS Son0ma 14.5