> Anything else you’d like me to look at here?

Attached find the changes I intend to push in the next few days plus a
ChangeLog.  You will find this particular change there:

+  f->output_data.ns->left_edge_cursor = [NSCursor resizeLeftRightCursor];
+  f->output_data.ns->top_left_corner_cursor = [NSCursor arrowCursor];
+  f->output_data.ns->top_edge_cursor = [NSCursor resizeUpDownCursor];
+  f->output_data.ns->top_right_corner_cursor = [NSCursor arrowCursor];
+  f->output_data.ns->right_edge_cursor = [NSCursor resizeLeftRightCursor];
+  f->output_data.ns->bottom_right_corner_cursor = [NSCursor arrowCursor];
+  f->output_data.ns->bottom_edge_cursor = [NSCursor resizeUpDownCursor];
+  f->output_data.ns->bottom_left_corner_cursor = [NSCursor arrowCursor];

It would be nice to have something better on NS for the
top_left_corner_cursor, top_right_corner_cursor,
bottom_right_corner_cursor and bottom_left_corner_cursor cases.

If you want to play around with child frames, try the attached file
my-child-frame.el.  Any feedback welcome.

Thanks in advance, martin