Coordinate checks in `spline_under_mouse_get` need to take place with the evaluated mask to get the right center. This is now more in line to how this is done in `ED_mask_point_find_nearest`. Note: similar issues are reported with box/circle/lasso selection in T97135, will tackle these separately though. Maniphest Tasks: T85467 Differential Revision: https://developer.blender.org/D14598