patch 8.2.3952: first line not redrawn when adding lines to an empty buffer Commit: https://github.com/vim/vim/commit/1fa3de1ce806ba18ebcc00c6d9a0678a84735463 Author: zeertzjq <zeertzjq@outlook.com> Date: Fri Dec 31 12:19:22 2021 +0000 patch 8.2.3952: first line not redrawn when adding lines to an empty buffer Problem: First line not redrawn when adding lines to an empty buffer. Solution: Adjust the argument to appended_lines(). (closes https://github.com/vim/vim/issues/9439, closes #9438)

--- a/src/ex_cmds.c
+++ b/src/ex_cmds.c
@@ -3359,7 +3359,11 @@ ex_append(exarg_T *eap)
 
 	did_undo = TRUE;
 	ml_append(lnum, theline, (colnr_T)0, FALSE);
-	appended_lines_mark(lnum + (empty ? 1 : 0), 1L);
+	if (empty)
+	    // there are no marks below the inserted lines
+	    appended_lines(lnum, 1L);
+	else
+	    appended_lines_mark(lnum, 1L);
 
 	vim_free(theline);
 	++lnum;