patch 9.0.1600: screenpos() does not take w_skipcol into account
Problem: screenpos() does not take w_skipcol into account.
Solution: Subtract w_skipcol from column. (closes #12486, closes #12476)
diff --git a/src/move.c b/src/move.c
index a113919..ff2f494 100644
--- a/src/move.c
+++ b/src/move.c
@@ -1479,6 +1479,9 @@
col += off;
width = wp->w_width - off + win_col_off2(wp);
+ if (pos->lnum == wp->w_topline)
+ col -= wp->w_skipcol;
+
// long line wrapping, adjust row
if (wp->w_p_wrap
&& col >= (colnr_T)wp->w_width