I just updated to Sequoia 15.4, and I see that the pointing hand that appears when the pointer is hovering over a link, document, etc., is now black with a white outline. Before 15.4, I think — emphasis on think — the hand was always white with a black outline, something like a Mickey Mouse gloved hand.
The Mac User Guide page about pointers still shows white glove, black outline. And the arrow pointer shown there is still black with a white outline. So it seems that the hand has been changed to match the cursor. Changing the outline and fill colors for pointers in System Settings changes them all. So a white glove with black outline also means a white I-beam with black outline — pretty ugly to my eyes.
Check the pointer colors in the Accessibility → Display system settings page. Maybe something changed them. If so, click the “Reset Colors” button to see if they change back.
I’ve tried changing colors several times. It’s always the same result: white arrow/black outline, white hand/black outline, or the other way round. There’s no way to get a black arrow/white outline and white hand/black outline, as the User Guide page shows.
