patch 8.2.2454: leading space can not be made visible
Problem: Leading space can not be made visible.
Solution: Add "lead:" to 'listchars'. (closes #7772)
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 8b655dc..74bab42 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -4877,6 +4877,10 @@
*lcs-space*
space:c Character to show for a space. When omitted, spaces
are left blank.
+ *lcs-lead*
+ lead:c Character to show for leading spaces. When omitted,
+ leading spaces are blank. Overrides the "space"
+ setting for leading spaces.
*lcs-trail*
trail:c Character to show for trailing spaces. When omitted,
trailing spaces are blank. Overrides the "space"