Problem: 'cursorline' not always updated with 'cursorlineopt' is "screenline". Solution: Call check_redraw_cursorline() more often. (closes vim/vim#10013) bf269ed0b0 Code was reverted in patch 8.2.4638, so this just ports the test.
bf269ed0b0
pending
CSI 4 : [2,4,5] m