Update runtime files
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 65ed54f..55e3cf8 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -1,4 +1,4 @@
-*options.txt*	For Vim version 8.2.  Last change: 2022 Jan 02
+*options.txt*	For Vim version 8.2.  Last change: 2022 Jan 22
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -170,7 +170,7 @@
 value will result in an error: >
 	:set t_kb=
 	:set t_kb
-	E846: Key code not set: t_kb
+<	E846: Key code not set: t_kb ~
 
 The t_xx options cannot be set from a |modeline| or in the |sandbox|, for
 security reasons.
@@ -1229,7 +1229,9 @@
 	the script ID (|local-function|). Example: >
 		set bexpr=s:MyBalloonExpr()
 		set bexpr=<SID>SomeBalloonExpr()
-<
+<	Otherwise, the expression is evaluated in the context of the script
+	where the option was set, thus script-local items are available.
+
 	The expression will be evaluated in the |sandbox| when set from a
 	modeline, see |sandbox-option|.
 	This option cannot be set in a modeline when 'modelineexpr' is off.
@@ -3439,7 +3441,9 @@
 			{not available when compiled without the |+folding|
 			or |+eval| features}
 	The expression used for when 'foldmethod' is "expr".  It is evaluated
-	for each line to obtain its fold level.  See |fold-expr|.
+	for each line to obtain its fold level.  The context is set to the
+	script where 'foldexpr' was set, script-local items can be accessed.
+	See |fold-expr| for the usage.
 
 	The expression will be evaluated in the |sandbox| if set from a
 	modeline, see |sandbox-option|.
@@ -3573,7 +3577,9 @@
 			{not available when compiled without the |+folding|
 			feature}
 	An expression which is used to specify the text displayed for a closed
-	fold.  See |fold-foldtext|.
+	fold.  The context is set to the script where 'foldexpr' was set,
+	script-local items can be accessed.  See |fold-foldtext| for the
+	usage.
 
 	The expression will be evaluated in the |sandbox| if set from a
 	modeline, see |sandbox-option|.
@@ -3616,7 +3622,9 @@
 	the script ID (|local-function|). Example: >
 		set formatexpr=s:MyFormatExpr()
 		set formatexpr=<SID>SomeFormatExpr()
-<
+<	Otherwise, the expression is evaluated in the context of the script
+	where the option was set, thus script-local items are available.
+
 	The expression will be evaluated in the |sandbox| when set from a
 	modeline, see |sandbox-option|.  That stops the option from working,
 	since changing the buffer text is not allowed.
@@ -4463,7 +4471,9 @@
 	the script ID (|local-function|). Example: >
 		set includeexpr=s:MyIncludeExpr(v:fname)
 		set includeexpr=<SID>SomeIncludeExpr(v:fname)
-<
+<	Otherwise, the expression is evaluated in the context of the script
+	where the option was set, thus script-local items are available.
+
 	The expression will be evaluated in the |sandbox| when set from a
 	modeline, see |sandbox-option|.
 	This option cannot be set in a modeline when 'modelineexpr' is off.
@@ -4537,11 +4547,14 @@
 	The expression is evaluated with |v:lnum| set to the line number for
 	which the indent is to be computed.  The cursor is also in this line
 	when the expression is evaluated (but it may be moved around).
+
 	If the expression starts with s: or |<SID>|, then it is replaced with
 	the script ID (|local-function|). Example: >
 		set indentexpr=s:MyIndentExpr()
 		set indentexpr=<SID>SomeIndentExpr()
-<
+<	Otherwise, the expression is evaluated in the context of the script
+	where the option was set, thus script-local items are available.
+
 	The expression must return the number of spaces worth of indent.  It
 	can return "-1" to keep the current indent (this means 'autoindent' is
 	used for the indent).
@@ -5685,7 +5698,7 @@
 			    *'opendevice'* *'odev'* *'noopendevice'* *'noodev'*
 'opendevice' 'odev'	boolean	(default off)
 			global
-			{only for MS-Windows}
+			{only for MS-Windows}  *E796*
 	Enable reading and writing from devices.  This may get Vim stuck on a
 	device that can be opened but doesn't actually do the I/O.  Therefore
 	it is off by default.