diff --git a/runtime/indent/cdl.vim b/runtime/indent/cdl.vim
index fb4fe27..0e3c615 100644
--- a/runtime/indent/cdl.vim
+++ b/runtime/indent/cdl.vim
@@ -1,5 +1,6 @@
 " Description:	Comshare Dimension Definition Language (CDL)
-" Author:	Raul Segura Acevedo <raulseguraaceved@netscape.net>
+" Maintainer:	Raul Segura Acevedo <raulseguraaceved@netscape.net> (Invalid email address)
+" 		Doug Kearns <dougkearns@gmail.com>
 " Last Change:	Fri Nov 30 13:35:48  2001 CST
 
 if exists("b:did_indent")
diff --git a/runtime/indent/cobol.vim b/runtime/indent/cobol.vim
index 590a729..01f7212 100644
--- a/runtime/indent/cobol.vim
+++ b/runtime/indent/cobol.vim
@@ -7,6 +7,7 @@
 " Ankit Jain      22.03.2019     Changes & fixes:
 "                                Allow chars in 1st 6 columns
 "                                #C22032019
+" Ankit Jain      24.09.2021     add b:undo_indent (request by tpope)
 
 if exists("b:did_indent")
     finish
@@ -18,6 +19,8 @@
 setlocal indentkeys&
 setlocal indentkeys+=0<*>,0/,0$,0=01,=~division,=~section,0=~end,0=~then,0=~else,0=~when,*<Return>,.
 
+let b:undo_indent = "setlocal expandtab< indentexpr< indentkeys<"
+
 " Only define the function once.
 if exists("*GetCobolIndent")
     finish
diff --git a/runtime/indent/config.vim b/runtime/indent/config.vim
index c987a78..b840b1e 100644
--- a/runtime/indent/config.vim
+++ b/runtime/indent/config.vim
@@ -1,9 +1,10 @@
 " Vim indent file
-" Language:             Autoconf configure.{ac,in} file
-" Previous Maintainer:  Nikolai Weibull <now@bitwi.se>
-" Latest Revision:      2006-12-20
-" TODO:                 how about nested [()]'s in one line
-"                   what's wrong with '\\\@!'?
+" Language:		Autoconf configure.{ac,in} file
+" Maintainer:		Doug Kearns <dougkearns@gmail.com>
+" Previous Maintainer:	Nikolai Weibull <now@bitwi.se>
+" Last Change:		24 Sep 2021
+
+" TODO: how about nested [()]'s in one line what's wrong with '\\\@!'?
 
 " Only load this indent file when no other was loaded.
 if exists("b:did_indent")
@@ -16,6 +17,8 @@
 setlocal indentkeys=!^F,o,O,=then,=do,=else,=elif,=esac,=fi,=fin,=fil,=done
 setlocal nosmartindent
 
+let b:undo_indent = "setl inde< indk< si<"
+
 " Only define the function once.
 if exists("*GetConfigIndent")
   finish
diff --git a/runtime/indent/css.vim b/runtime/indent/css.vim
index 4d15b8d..793f058 100644
--- a/runtime/indent/css.vim
+++ b/runtime/indent/css.vim
@@ -1,8 +1,10 @@
 " Vim indent file
-" Language:	    CSS
-" Maintainer:	    Nikolai Weibull <now@bitwi.se>
-" Latest Revision:  2012-05-30
-"		    Use of shiftwidth() added by Oleg Zubchenko.	
+" Language:		CSS
+" Maintainer:		Doug Kearns <dougkearns@gmail.com>
+" Previous Maintainer:	Nikolai Weibull <now@bitwi.se>
+" Last Change:		24 Sep 2021
+
+" Use of shiftwidth() added by Oleg Zubchenko.
 
 if exists("b:did_indent")
   finish
@@ -13,7 +15,7 @@
 setlocal indentkeys=0{,0},!^F,o,O
 setlocal nosmartindent
 
-let b:undo_indent = "setl smartindent< indentkeys< indentexpr<"
+let b:undo_indent = "setl inde< indk< si<"
 
 if exists("*GetCSSIndent")
   finish
diff --git a/runtime/indent/d.vim b/runtime/indent/d.vim
index b5dd5e8..57f9125 100644
--- a/runtime/indent/d.vim
+++ b/runtime/indent/d.vim
@@ -1,7 +1,7 @@
 " Vim indent file for the D programming language (version 0.137).
-"
 " Language:	D
-" Maintainer:	Jason Mills<jmills@cs.mun.ca>
+" Maintainer:	Jason Mills <jmills@cs.mun.ca> (Invalid email address)
+" 		Doug Kearns <dougkearns@gmail.com>
 " Last Change:	2005 Nov 22
 " Version:	0.1
 "
diff --git a/runtime/indent/dtd.vim b/runtime/indent/dtd.vim
index 30c06aa..c2b3c0c 100644
--- a/runtime/indent/dtd.vim
+++ b/runtime/indent/dtd.vim
@@ -1,12 +1,15 @@
 " Vim indent file
-" Language:    	    DTD (Document Type Definition for XML)
-" Previous Maintainer:  Nikolai Weibull <now@bitwi.se>
-" Latest Revision:      2011-07-08
+" Language:		DTD (Document Type Definition for XML)
+" Maintainer:		Doug Kearns <dougkearns@gmail.com>
+" Previous Maintainer:	Nikolai Weibull <now@bitwi.se>
+" Last Change:		24 Sep 2021
 
 setlocal indentexpr=GetDTDIndent()
 setlocal indentkeys=!^F,o,O,>
 setlocal nosmartindent
 
+let b:undo_indent = "setl inde< indk< si<"
+
 if exists("*GetDTDIndent")
   finish
 endif
diff --git a/runtime/indent/dylan.vim b/runtime/indent/dylan.vim
index 6811ec4..55255dd 100644
--- a/runtime/indent/dylan.vim
+++ b/runtime/indent/dylan.vim
@@ -1,8 +1,9 @@
 " Vim indent file
 " Language:	Dylan
+" Maintainer:	Brent A. Fulgham <bfulgham@debian.org> (Invalid email address)
+" 		Doug Kearns <dougkearns@gmail.com>
 " Version:	0.01
 " Last Change:	2017 Jun 13
-" Maintainer:	Brent A. Fulgham <bfulgham@debian.org>
 
 " Only load this indent file when no other was loaded.
 if exists("b:did_indent")
diff --git a/runtime/indent/elm.vim b/runtime/indent/elm.vim
index 232c347..7b08de7 100644
--- a/runtime/indent/elm.vim
+++ b/runtime/indent/elm.vim
@@ -4,7 +4,7 @@
 " Original Author: Joseph Hager <ajhager@gmail.com>
 " Copyright: Joseph Hager <ajhager@gmail.com>
 " License: BSD3
-" Latest Revision: 2020-05-29
+" Latest Revision: 2021-09-29
 
 " Only load this indent file when no other was loaded.
 if exists('b:did_indent')
@@ -19,6 +19,8 @@
 setlocal nolisp
 setlocal nosmartindent
 
+let b:undo_indent = "setl et< inde< indk< lisp< si<"
+
 " Only define the function once.
 if exists('*GetElmIndent')
 	finish
diff --git a/runtime/indent/eterm.vim b/runtime/indent/eterm.vim
index 8ee342f..3accf9b 100644
--- a/runtime/indent/eterm.vim
+++ b/runtime/indent/eterm.vim
@@ -1,7 +1,8 @@
 " Vim indent file
-" Language:             Eterm configuration file
-" Previous Maintainer:  Nikolai Weibull <now@bitwi.se>
-" Latest Revision:      2006-12-20
+" Language:		Eterm configuration file
+" Maintainer:		Doug Kearns <dougkearns@gmail.com>
+" Previous Maintainer:	Nikolai Weibull <now@bitwi.se>
+" Last Change:		24 Sep 2021
 
 if exists("b:did_indent")
   finish
@@ -12,6 +13,8 @@
 setlocal indentkeys=!^F,o,O,=end
 setlocal nosmartindent
 
+let b:undo_indent = "setl inde< indk< si<"
+
 if exists("*GetEtermIndent")
   finish
 endif
diff --git a/runtime/indent/framescript.vim b/runtime/indent/framescript.vim
index f9a274e..4611d34 100644
--- a/runtime/indent/framescript.vim
+++ b/runtime/indent/framescript.vim
@@ -1,7 +1,8 @@
 " Vim indent file
-" Language:             FrameScript
-" Previous Maintainer:  Nikolai Weibull <now@bitwi.se>
-" Latest Revision:      2008-07-19
+" Language:		FrameScript
+" Maintainer:		Doug Kearns <dougkearns@gmail.com>
+" Previous Maintainer:	Nikolai Weibull <now@bitwi.se>
+" Last Change:		24 Sep 2021
 
 if exists("b:did_indent")
   finish
@@ -12,6 +13,8 @@
 setlocal indentkeys=!^F,o,O,0=~Else,0=~EndIf,0=~EndLoop,0=~EndSub
 setlocal nosmartindent
 
+let b:undo_indent = "setl inde< indk< si<"
+
 if exists("*GetFrameScriptIndent")
   finish
 endif
diff --git a/runtime/indent/idlang.vim b/runtime/indent/idlang.vim
index 7402e86..e6a1d73 100644
--- a/runtime/indent/idlang.vim
+++ b/runtime/indent/idlang.vim
@@ -1,7 +1,8 @@
 " IDL (Interactive Data Language) indent file.
-" Language: IDL (ft=idlang)
+" Language:	IDL (ft=idlang)
+" Maintainer:	Aleksandar Jelenak <ajelenak AT yahoo.com> (Invalid email address)
+" 		Doug Kearns <dougkearns@gmail.com>
 " Last change:	2017 Jun 13
-" Maintainer: Aleksandar Jelenak <ajelenak AT yahoo.com>
 
 " Only load this indent file when no other was loaded.
 if exists("b:did_indent")
diff --git a/runtime/indent/ld.vim b/runtime/indent/ld.vim
index a72a3a9..ddf003e 100644
--- a/runtime/indent/ld.vim
+++ b/runtime/indent/ld.vim
@@ -1,7 +1,8 @@
 " Vim indent file
-" Language:             ld(1) script
-" Previous Maintainer:  Nikolai Weibull <now@bitwi.se>
-" Latest Revision:      2006-12-20
+" Language:		ld(1) script
+" Maintainer:		Doug Kearns <dougkearns@gmail.com>
+" Previous Maintainer:	Nikolai Weibull <now@bitwi.se>
+" Last Change:		24 Sep 2021
 
 if exists("b:did_indent")
   finish
@@ -12,6 +13,8 @@
 setlocal indentkeys=0{,0},!^F,o,O
 setlocal nosmartindent
 
+let b:undo_indent = "setl inde< indk< si<"
+
 if exists("*GetLDIndent")
   finish
 endif
diff --git a/runtime/indent/mail.vim b/runtime/indent/mail.vim
index 6246b40..22bb0f7 100644
--- a/runtime/indent/mail.vim
+++ b/runtime/indent/mail.vim
@@ -1,7 +1,7 @@
 " Vim indent file
 " Language:	Mail
 " Maintainer:	Bram Moolenaar
-" Last Change:	2009 Jun 03
+" Last Change:	2021 Sep 26
 
 if exists("b:did_indent")
   finish
@@ -11,3 +11,5 @@
 " What works best is auto-indenting, disable other indenting.
 " For formatting see the ftplugin.
 setlocal autoindent nosmartindent nocindent indentexpr=
+
+let b:undo_indent = "setl ai< cin< inde< si<"
diff --git a/runtime/indent/make.vim b/runtime/indent/make.vim
index 4483efd..76c8f83 100644
--- a/runtime/indent/make.vim
+++ b/runtime/indent/make.vim
@@ -1,7 +1,8 @@
 " Vim indent file
-" Language:             Makefile
-" Previous Maintainer:  Nikolai Weibull <now@bitwi.se>
-" Latest Revision:      2007-05-07
+" Language:		Makefile
+" Maintainer:		Doug Kearns <dougkearns@gmail.com>
+" Previous Maintainer:	Nikolai Weibull <now@bitwi.se>
+" Last Change:		24 Sep 2021
 
 if exists("b:did_indent")
   finish
@@ -12,6 +13,8 @@
 setlocal indentkeys=!^F,o,O,<:>,=else,=endif
 setlocal nosmartindent
 
+let b:undo_indent = "setl ai< inde< indk<"
+
 if exists("*GetMakeIndent")
   finish
 endif
diff --git a/runtime/indent/matlab.vim b/runtime/indent/matlab.vim
index 6390445..10d8460 100644
--- a/runtime/indent/matlab.vim
+++ b/runtime/indent/matlab.vim
@@ -2,6 +2,7 @@
 " Language: MATLAB
 " Maintainer: Axel Forsman <axelsfor@gmail.com>
 " Previous maintainer: Christophe Poucet <christophe.poucet@pandora.be>
+" Last Update: 2021-10-01
 
 " Only load if no other indent file is loaded
 if exists('b:did_indent') | finish | endif
@@ -9,6 +10,7 @@
 
 setlocal indentexpr=GetMatlabIndent()
 setlocal indentkeys=!,o,O,e,0=end,0=elseif,0=case,0=otherwise,0=catch,0=function,0=elsei
+let b:undo_indent = "setlocal indentexpr< indentkeys<"
 
 " The value of the Function indenting format in
 " MATLAB Editor/Debugger Language Preferences.
diff --git a/runtime/indent/mma.vim b/runtime/indent/mma.vim
index a76fa8e..ebf98b9 100644
--- a/runtime/indent/mma.vim
+++ b/runtime/indent/mma.vim
@@ -1,9 +1,10 @@
 " Vim indent file
-" Language:     Mathematica
-" Author:       steve layland <layland@wolfram.com>
-" Last Change:  Sat May  10 18:56:22 CDT 2005
-" Source:       http://vim.sourceforge.net/scripts/script.php?script_id=1274
-"               http://members.wolfram.com/layland/vim/indent/mma.vim
+" Language:	Mathematica
+" Maintainer:	Steve Layland <layland@wolfram.com> (Invalid email address)
+" 		Doug Kearns <dougkearns@gmail.com>
+" Last Change:	Sat May  10 18:56:22 CDT 2005
+" Source:	http://vim.sourceforge.net/scripts/script.php?script_id=1274
+" 		http://members.wolfram.com/layland/vim/indent/mma.vim
 "
 " NOTE:
 " Empty .m files will automatically be presumed to be Matlab files
diff --git a/runtime/indent/nginx.vim b/runtime/indent/nginx.vim
new file mode 100644
index 0000000..d4afec1
--- /dev/null
+++ b/runtime/indent/nginx.vim
@@ -0,0 +1,17 @@
+" Vim indent file
+" Language: nginx.conf
+" Maintainer: Chris Aumann <me@chr4.org>
+" Last Change: Apr 15, 2017
+
+if exists("b:did_indent")
+    finish
+endif
+let b:did_indent = 1
+
+setlocal indentexpr=
+
+" cindent actually works for nginx' simple file structure
+setlocal cindent
+
+" Just make sure that the comments are not reset as defs would be.
+setlocal cinkeys-=0#
diff --git a/runtime/indent/occam.vim b/runtime/indent/occam.vim
index 4acd42e..2979ac1 100644
--- a/runtime/indent/occam.vim
+++ b/runtime/indent/occam.vim
@@ -1,6 +1,7 @@
 " Vim indent file
 " Language:	occam
-" Maintainer:	Mario Schweigler <ms44@kent.ac.uk>
+" Maintainer:	Mario Schweigler <ms44@kent.ac.uk> (Invalid email address)
+" 		Doug Kearns <dougkearns@gmail.com>
 " Last Change:	23 April 2003
 
 " Only load this indent file when no other was loaded.
diff --git a/runtime/indent/pascal.vim b/runtime/indent/pascal.vim
index 1f39fd1..b21b725 100644
--- a/runtime/indent/pascal.vim
+++ b/runtime/indent/pascal.vim
@@ -2,11 +2,9 @@
 " Language:    Pascal
 " Maintainer:  Neil Carter <n.carter@swansea.ac.uk>
 " Created:     2004 Jul 13
-" Last Change: 2021 Jul 01
+" Last Change: 2021 Sep 22
 "
-" This is version 2.0, a complete rewrite.
-"
-" For further documentation, see http://psy.swansea.ac.uk/staff/carter/vim/
+" For further documentation, see https://psy.swansea.ac.uk/staff/carter/vim/
 
 
 if exists("b:did_indent")
@@ -20,13 +18,14 @@
 setlocal indentkeys+==program,==function,==procedure,==object,==private
 setlocal indentkeys+==record,==if,==else,==case
 
-let b:undo_indent = "setl indentkeys< indentexpr<"
+let b:undo_indent = 'setlocal indentexpr< indentkeys<'
 
 if exists("*GetPascalIndent")
 	finish
 endif
 
 
+" ________________________________________________________________
 function! s:GetPrevNonCommentLineNum( line_num )
 
 	" Skip lines starting with a comment
@@ -44,6 +43,7 @@
 endfunction
 
 
+" ________________________________________________________________
 function! s:PurifyCode( line_num )
 	" Strip any trailing comments and whitespace
 	let pureline = 'TODO'
@@ -51,6 +51,7 @@
 endfunction
 
 
+" ________________________________________________________________
 function! GetPascalIndent( line_num )
 
 	" Line 0 always goes at column 0
@@ -184,7 +185,7 @@
 	endif
 
 
-" ____________________________________________________________________
+" ________________________________________________________________
 " Object/Borland Pascal/Delphi Extensions
 "
 " Note that extended-pascal is handled here, unless it is simpler to
@@ -222,8 +223,6 @@
 	endif
 
 
-" ____________________________________________________________________
-
 	" If nothing changed, return same indent.
 	return indnt
 endfunction
diff --git a/runtime/indent/postscr.vim b/runtime/indent/postscr.vim
index 2592bcf..0691cd2 100644
--- a/runtime/indent/postscr.vim
+++ b/runtime/indent/postscr.vim
@@ -1,7 +1,8 @@
 " PostScript indent file
-" Language:    PostScript
-" Maintainer:  Mike Williams <mrw@netcomuk.co.uk>
-" Last Change: 2nd July 2001
+" Language:	PostScript
+" Maintainer:	Mike Williams <mrw@netcomuk.co.uk> (Invalid email address)
+" 		Doug Kearns <dougkearns@gmail.com>
+" Last Change:	2nd July 2001
 "
 
 " Only load this indent file when no other was loaded.
diff --git a/runtime/indent/prolog.vim b/runtime/indent/prolog.vim
index ecd0894..ac03c28 100644
--- a/runtime/indent/prolog.vim
+++ b/runtime/indent/prolog.vim
@@ -1,7 +1,8 @@
 "  vim: set sw=4 sts=4:
-"  Maintainer	: Gergely Kontra <kgergely@mcl.hu>
-"  Revised on	: 2002.02.18. 23:34:05
-"  Language	: Prolog
+"  Language:	Prolog
+"  Maintainer:	Gergely Kontra <kgergely@mcl.hu> (Invalid email address)
+" 		Doug Kearns <dougkearns@gmail.com>
+"  Revised on:	2002.02.18. 23:34:05
 "  Last change by: Takuya Fujiwara, 2018 Sep 23
 
 " TODO:
diff --git a/runtime/indent/python.vim b/runtime/indent/python.vim
index 307b7f6..6681229 100644
--- a/runtime/indent/python.vim
+++ b/runtime/indent/python.vim
@@ -2,7 +2,7 @@
 " Language:		Python
 " Maintainer:		Bram Moolenaar <Bram@vim.org>
 " Original Author:	David Bustos <bustos@caltech.edu>
-" Last Change:		2021 May 26
+" Last Change:		2021 Sep 26
 
 " Only load this indent file when no other was loaded.
 if exists("b:did_indent")
@@ -17,6 +17,8 @@
 setlocal indentexpr=GetPythonIndent(v:lnum)
 setlocal indentkeys+=<:>,=elif,=except
 
+let b:undo_indent = "setl ai< inde< indk< lisp<"
+
 " Only define the function once.
 if exists("*GetPythonIndent")
   finish
diff --git a/runtime/indent/readline.vim b/runtime/indent/readline.vim
index e202ddf..0ab0f82 100644
--- a/runtime/indent/readline.vim
+++ b/runtime/indent/readline.vim
@@ -1,7 +1,8 @@
 " Vim indent file
-" Language:             readline configuration file
-" Previous Maintainer:  Nikolai Weibull <now@bitwi.se>
-" Latest Revision:      2006-12-20
+" Language:		readline configuration file
+" Maintainer:		Doug Kearns <dougkearns@gmail.com>
+" Previous Maintainer:	Nikolai Weibull <now@bitwi.se>
+" Last Change:		24 Sep 2021
 
 if exists("b:did_indent")
   finish
@@ -12,6 +13,8 @@
 setlocal indentkeys=!^F,o,O,=$else,=$endif
 setlocal nosmartindent
 
+let b:undo_indent = "setl inde< indk< si<"
+
 if exists("*GetReadlineIndent")
   finish
 endif
diff --git a/runtime/indent/sdl.vim b/runtime/indent/sdl.vim
index 6ce30b6..40fe63f 100644
--- a/runtime/indent/sdl.vim
+++ b/runtime/indent/sdl.vim
@@ -1,7 +1,7 @@
 " Vim indent file
 " Language:	SDL
 " Maintainer:	Michael Piefel <entwurf@piefel.de>
-" Last Change:	10 December 2011
+" Last Change:	2021 Oct 03
 
 " Shamelessly stolen from the Vim-Script indent file
 
@@ -14,6 +14,8 @@
 setlocal indentexpr=GetSDLIndent()
 setlocal indentkeys+==~end,=~state,*<Return>
 
+let b:undo_indent = "setl inde< indk<"
+
 " Only define the function once.
 if exists("*GetSDLIndent")
 "  finish
diff --git a/runtime/indent/tcl.vim b/runtime/indent/tcl.vim
index eafb8dd..c35150d 100644
--- a/runtime/indent/tcl.vim
+++ b/runtime/indent/tcl.vim
@@ -1,8 +1,8 @@
 " Vim indent file
-" Language:	    	Tcl
-" Latest Update:  	Chris Heithoff <chrisheithoff@gmail.com>
+" Language:		Tcl
+" Maintainer:		Chris Heithoff <chrisheithoff@gmail.com>
 " Previous Maintainer:	Nikolai Weibull <now@bitwi.se>
-" Latest Revision:      2018-12-05
+" Last Change:		24 Sep 2021
 
 if exists("b:did_indent")
   finish
@@ -13,6 +13,8 @@
 setlocal indentkeys=0{,0},!^F,o,O,0]
 setlocal nosmartindent
 
+let b:undo_indent = "setl inde< indk< si<"
+
 if exists("*GetTclIndent")
   finish
 endif
diff --git a/runtime/indent/tcsh.vim b/runtime/indent/tcsh.vim
index ed08e6c..025d9c8 100644
--- a/runtime/indent/tcsh.vim
+++ b/runtime/indent/tcsh.vim
@@ -1,7 +1,7 @@
 " Vim indent file
 " Language:		C-shell (tcsh)
-" Maintainer:		GI <a@b.c>, where a='gi1242+vim', b='gmail', c='com'
-" Last Modified:	Sat 10 Dec 2011 09:23:00 AM EST
+" Maintainer:		Doug Kearns <a@b.com> where a=dougkearns, b=gmail
+" Last Modified:	Sun 26 Sep 2021 12:38:38 PM EDT
 
 " Only load this indent file when no other was loaded.
 if exists("b:did_indent")
@@ -12,6 +12,7 @@
 
 setlocal indentexpr=TcshGetIndent()
 setlocal indentkeys+=e,0=end,0=endsw indentkeys-=0{,0},0),:,0#
+let b:undo_indent = "setl inde< indk<"
 
 " Only define the function once.
 if exists("*TcshGetIndent")
diff --git a/runtime/indent/zimbu.vim b/runtime/indent/zimbu.vim
index 5451877..0e6e2ab 100644
--- a/runtime/indent/zimbu.vim
+++ b/runtime/indent/zimbu.vim
@@ -1,7 +1,7 @@
 " Vim indent file
 " Language:	Zimbu
 " Maintainer:	Bram Moolenaar <Bram@vim.org>
-" Last Change:	2016 Jan 25
+" Last Change:	2021 Sep 26
 
 " Only load this indent file when no other was loaded.
 if exists("b:did_indent")
@@ -16,7 +16,7 @@
 " We impose recommended defaults: no Tabs, 'shiftwidth' = 2
 setlocal sw=2 et
 
-let b:undo_indent = "setl et< sw< ai< indentkeys< indentexpr="
+let b:undo_indent = "setl ai< cin< et< indentkeys< indentexpr< lisp< sw<"
 
 " Only define the function once.
 if exists("*GetZimbuIndent")