13 files changed, 205 insertions, 177 deletions
diff --git a/runtime/syntax/coco.vim b/runtime/syntax/coco.vim
index ae32348bcb..dc21314e35 100644
--- a/runtime/syntax/coco.vim
+++ b/runtime/syntax/coco.vim
@@ -1,7 +1,7 @@
 " Vim syntax file
 " Language:     Coco/R
 " Maintainer:   Ashish Shukla <wahjava@gmail.com>
-" Last Change:  2007 Aug 10
+" Last Change:  2022 Jun 14
 " Remark:       Coco/R syntax partially implemented.
 " License:      Vim license
 
@@ -30,3 +30,4 @@ hi def link cocoOperator         Operator
 hi def link cocoProductionCode   Statement
 hi def link cocoPragma           Special
 
+let b:current_syntax = 'coco'
diff --git a/runtime/syntax/dirpager.vim b/runtime/syntax/dirpager.vim
index 40137e4936..e93420f3ab 100644
--- a/runtime/syntax/dirpager.vim
+++ b/runtime/syntax/dirpager.vim
@@ -6,7 +6,7 @@
 " Description:	  display directory content inside Vim with syntax
 "		  highlighting
 " File:		  runtime/syntax/dirpager.vim
-" Last Change:	  2012 May 19
+" Last Change:	  2022 Jun 14
 " Modeline:	  vim: ts=8:sw=2:sts=2:
 "
 " Credits:	  dirpager.vim is derived from Nikolai Weibulls dircolors.vim
diff --git a/runtime/syntax/dts.vim b/runtime/syntax/dts.vim
index d75b9c178a..be51ab5b10 100644
--- a/runtime/syntax/dts.vim
+++ b/runtime/syntax/dts.vim
@@ -1,11 +1,12 @@
 " Vim syntax file
 " Language:	dts/dtsi (device tree files)
 " Maintainer:	Daniel Mack <vim@zonque.org>
-" Last Change:	2021 May 15
+" Last Change:	2022 Jun 14
 
 if exists("b:current_syntax")
   finish
 endif
+let b:current_syntax = 'dts'
 
 syntax region dtsComment        start="/\*"  end="\*/"
 syntax match  dtsReference      "&[[:alpha:][:digit:]_]\+"
diff --git a/runtime/syntax/icon.vim b/runtime/syntax/icon.vim
index 179d75cd28..276bb58497 100644
--- a/runtime/syntax/icon.vim
+++ b/runtime/syntax/icon.vim
@@ -1,199 +1,211 @@
 " Vim syntax file
-" Language:	Icon
-" Maintainer:	Wendell Turner <wendell@adsi-m4.com>
-" URL:		ftp://ftp.halcyon.com/pub/users/wturner/icon.vim
-" Last Change:	2003 May 11
+" Language:		Icon
+" Maintainer:		Doug Kearns <dougkearns@gmail.com>
+" Previous Maintainer:	Wendell Turner <wendell@adsi-m4.com> (invalid last known address)
+" Last Change:		2022 Jun 16
+" Contributor:		eschen@alumni.princeton.edu 2002.09.18
 
-" quit when a syntax file was already loaded
+" Prelude {{{1
 if exists("b:current_syntax")
   finish
 endif
 
-syn keyword  iconFunction   abs acos any args asin atan bal
-syn keyword  iconFunction   callout center char chdir close collect copy
-syn keyword  iconFunction   cos cset delay delete detab display dtor
-syn keyword  iconFunction   entab errorclear exit exp find flush function
-syn keyword  iconFunction   get getch getche getenv iand icom image
-syn keyword  iconFunction   insert integer ior ishift ixor kbhit key
-syn keyword  iconFunction   left list loadfunc log many map match
-syn keyword  iconFunction   member move name numeric open ord pop
-syn keyword  iconFunction   pos proc pull push put read reads
-syn keyword  iconFunction   real remove rename repl reverse right rtod
-syn keyword  iconFunction   runerr save seek seq set sin sort
-syn keyword  iconFunction   sortf sqrt stop string system tab table
-syn keyword  iconFunction   tan trim type upto variable where write writes
-
-" Keywords
-syn match iconKeyword "&allocated"
-syn match iconKeyword "&ascii"
-syn match iconKeyword "&clock"
-syn match iconKeyword "&collections"
-syn match iconKeyword "&cset"
-syn match iconKeyword "&current"
-syn match iconKeyword "&date"
-syn match iconKeyword "&dateline"
-syn match iconKeyword "&digits"
-syn match iconKeyword "&dump"
-syn match iconKeyword "&e"
-syn match iconKeyword "&error"
-syn match iconKeyword "&errornumber"
-syn match iconKeyword "&errortext"
-syn match iconKeyword "&errorvalue"
-syn match iconKeyword "&errout"
-syn match iconKeyword "&fail"
-syn match iconKeyword "&features"
-syn match iconKeyword "&file"
-syn match iconKeyword "&host"
-syn match iconKeyword "&input"
-syn match iconKeyword "&lcase"
-syn match iconKeyword "&letters"
-syn match iconKeyword "&level"
-syn match iconKeyword "&line"
-syn match iconKeyword "&main"
-syn match iconKeyword "&null"
-syn match iconKeyword "&output"
-syn match iconKeyword "&phi"
-syn match iconKeyword "&pi"
-syn match iconKeyword "&pos"
-syn match iconKeyword "&progname"
-syn match iconKeyword "&random"
-syn match iconKeyword "&regions"
-syn match iconKeyword "&source"
-syn match iconKeyword "&storage"
-syn match iconKeyword "&subject"
-syn match iconKeyword "&time"
-syn match iconKeyword "&trace"
-syn match iconKeyword "&ucase"
-syn match iconKeyword "&version"
-
-" Reserved words
-syn keyword iconReserved break by case create default do
-syn keyword iconReserved else end every fail if
-syn keyword iconReserved initial link next not of
-syn keyword iconReserved procedure repeat return suspend
-syn keyword iconReserved then to until while
-
-" Storage class reserved words
-syn keyword	iconStorageClass	global static local record
-
-syn keyword	iconTodo	contained TODO FIXME XXX BUG
-
-" String and Character constants
-" Highlight special characters (those which have a backslash) differently
-syn match iconSpecial contained "\\x\x\{2}\|\\\o\{3\}\|\\[bdeflnrtv\"\'\\]\|\\^c[a-zA-Z0-9]\|\\$"
-syn region	iconString	start=+"+ skip=+\\\\\|\\"+ end=+"+ contains=iconSpecial
-syn region	iconCset	start=+'+ skip=+\\\\\|\\'+ end=+'+ contains=iconSpecial
-syn match	iconCharacter	"'[^\\]'"
-
-" not sure about these
-"syn match	iconSpecialCharacter "'\\[bdeflnrtv]'"
-"syn match	iconSpecialCharacter "'\\\o\{3\}'"
-"syn match	iconSpecialCharacter "'\\x\x\{2}'"
-"syn match	iconSpecialCharacter "'\\^c\[a-zA-Z0-9]'"
-
-"when wanted, highlight trailing white space
+syn iskeyword @,48-57,_,192-255,&
+
+" Not Top {{{1
+syn cluster iconNotTop contains=iconDocField,iconIncluded,iconStringSpecial,iconTodo,@Spell
+
+" Whitespace errors {{{1
 if exists("icon_space_errors")
-  syn match	iconSpaceError	"\s*$"
-  syn match	iconSpaceError	" \+\t"me=e-1
+  if !exists("icon_no_trail_space_error")
+    syn match iconSpaceError "\s\+$"       display excludenl
+  endif
+  if !exists("icon_no_tab_space_error")
+    syn match iconSpaceError " \+\t"me=e-1 display
+  endif
 endif
 
-"catch errors caused by wrong parenthesis
-syn cluster	iconParenGroup contains=iconParenError,iconIncluded,iconSpecial,iconTodo,iconUserCont,iconUserLabel,iconBitField
+" Reserved words {{{1
+syn keyword iconReserved break by case create default do else every fail if
+syn keyword iconReserved initial next not of repeat return suspend then to
+syn keyword iconReserved until while
 
-syn region	iconParen	transparent start='(' end=')' contains=ALLBUT,@iconParenGroup
-syn match	iconParenError	")"
-syn match	iconInParen	contained "[{}]"
+syn keyword iconStorageClass global static local record invocable
 
+syn keyword iconLink link
 
-syn case ignore
+" Procedure definitions {{{1
+if exists("icon_no_procedure_fold")
+  syn region iconProcedure matchgroup=iconReserved start="\<procedure\>" end="\<end\>" contains=ALLBUT,@iconNotTop
+else
+  syn region iconProcedure matchgroup=iconReserved start="\<procedure\>" end="\<end\>" contains=ALLBUT,@iconNotTop fold
+endif
 
-"integer number, or floating point number without a dot
-syn match	iconNumber		"\<\d\+\>"
+" Keywords {{{1
+syn keyword iconKeyword &allocated &ascii &clock &collections &cset &current
+syn keyword iconKeyword &date &dateline &digits &dump &e &error &errornumber
+syn keyword iconKeyword &errortext &errorvalue &errout &fail &features &file
+syn keyword iconKeyword &host &input &lcase &letters &level &line &main &null
+syn keyword iconKeyword &output &phi &pi &pos &progname &random &regions
+syn keyword iconKeyword &source &storage &subject &time &trace &ucase &version
+
+" Graphics keywords
+syn keyword iconKeyword &col &control &interval &ldrag &lpress &lrelease
+syn keyword iconKeyword &mdrag &meta &mpress &mrelease &rdrag &resize &row
+syn keyword iconKeyword &rpress &rrelease &shift &window &x &y
+
+" Functions {{{1
+syn keyword iconFunction abs acos any args asin atan bal callout center char
+syn keyword iconFunction chdir close collect copy cos cset delay delete detab
+syn keyword iconFunction display dtor entab errorclear exit exp find flush
+syn keyword iconFunction function get getch getche getenv iand icom image
+syn keyword iconFunction insert integer ior ishift ixor kbhit key left list
+syn keyword iconFunction loadfunc log many map match member move name numeric
+syn keyword iconFunction open ord pop pos proc pull push put read reads real
+syn keyword iconFunction remove rename repl reverse right rtod runerr save
+syn keyword iconFunction seek self seq serial set sin sort sortf sqrt stop
+syn keyword iconFunction string system tab table tan trim type upto variable
+syn keyword iconFunction where write writes
+
+" Graphics functions
+syn keyword iconFunction Active Alert Bg CenterString Clip Clone Color
+syn keyword iconFunction ColorDialog ColorValue CopyArea Couple DrawArc
+syn keyword iconFunction DrawCircle DrawCurve DrawImage DrawLine DrawPoint
+syn keyword iconFunction DrawPolygon DrawRectangle DrawSegment DrawString
+syn keyword iconFunction Enqueue EraseArea Event Fg FillArc FillCircle
+syn keyword iconFunction FillPolygon FillRectangle Font FreeColor GotoRC
+syn keyword iconFunction GotoXY LeftString Lower NewColor Notice OpenDialog
+syn keyword iconFunction PaletteChars PaletteColor PaletteGrays PaletteKey
+syn keyword iconFunction Pattern Pending Pixel Raise ReadImage RightString
+syn keyword iconFunction SaveDialog SelectDialog Shade TextDialog TextWidth
+syn keyword iconFunction ToggleDialog Uncouple WAttrib WClose WDefault WDelay
+syn keyword iconFunction WDone WFlush WOpen WQuit WRead WReads WriteImage
+syn keyword iconFunction WSync WWrite WWrites
+
+" String and character constants {{{1
+syn match  iconStringSpecial "\\x\x\{2}\|\\\o\{3\}\|\\[bdeflnrtv\"\'\\]\|\\^[a-zA-Z0-9]" contained 
+syn match  iconStringSpecial "\\$"							 contained
+syn match  iconStringSpecial "_\ze\s*$"						         contained
+
+syn region iconString start=+"+ skip=+\\\\\|\\"+ end=+"+ contains=iconStringSpecial
+syn region iconCset   start=+'+ skip=+\\\\\|\\'+ end=+'+ contains=iconStringSpecial
+
+" Bracket errors {{{1
+
+if !exists("icon_no_bracket_errors")
+  " catch errors caused by wrong brackets (ACE 2002.09.18)
+  syn cluster iconBracketGroup contains=iconBracketError,iconIncluded
+  syn region  iconBracket      start='\[' end='\]' contains=ALLBUT,@iconBracketGroup,@iconNotTop transparent 
+  syn match   iconBracketError "]"
+  
+  "catch errors caused by wrong braces (ACE 2002.09.18)
+  syn cluster iconBraceGroup contains=iconBraceError,iconIncluded
+  syn region  iconBrace	     start='{' end='}' contains=ALLBUT,@iconBraceGroup,@iconNotTop transparent 
+  syn match   iconBraceError "}"
+  
+  "catch errors caused by wrong parenthesis
+  syn cluster iconParenGroup contains=iconParenError,iconIncluded
+  syn region  iconParen	     start='(' end=')' contains=ALLBUT,@iconParenGroup,@iconNotTop transparent 
+  syn match   iconParenError ")"
+end
+
+" Numbers {{{1
+syn case ignore
 
-"floating point number, with dot, optional exponent
-syn match	iconFloat		"\<\d\+\.\d*\(e[-+]\=\d\+\)\=\>"
+" integer
+syn match iconInteger "\<\d\+\>"
+syn match iconInteger "\<\d\{1,2}[rR][a-zA-Z0-9]\+\>"
 
-"floating point number, starting with a dot, optional exponent
-syn match	iconFloat		"\.\d\+\(e[-+]\=\d\+\)\=\>"
+" real with trailing dot
+syn match iconReal    "\<\d\+\."
 
-"floating point number, without dot, with exponent
-syn match	iconFloat		"\<\d\+e[-+]\=\d\+\>"
+" real, with dot, optional exponent
+syn match iconReal    "\<\d\+\.\d*\%(e[-+]\=\d\+\)\=\>"
 
-"radix number
-syn match	iconRadix		"\<\d\{1,2}[rR][a-zA-Z0-9]\+\>"
+" real, with leading dot, optional exponent
+syn match iconReal    "\.\d\+\%(e[-+]\=\d\+\)\=\>"
 
+" real, without dot, with exponent
+syn match iconReal    "\<\d\+e[-+]\=\d\+\>"
 
-" syn match iconIdentifier	"\<[a-z_][a-z0-9_]*\>"
+syn cluster iconNumber contains=iconInteger,iconReal
 
 syn case match
 
-" Comment
-syn match	iconComment	"#.*" contains=iconTodo,iconSpaceError
-
-syn region	iconPreCondit start="^\s*$\s*\(if\>\|ifdef\>\|ifndef\>\|elif\>\|else\>\|endif\>\)" skip="\\$" end="$" contains=iconComment,iconString,iconCharacter,iconNumber,iconCommentError,iconSpaceError
-
-syn region	iconIncluded	contained start=+"+ skip=+\\\\\|\\"+ end=+"+
-syn match	iconIncluded	contained "<[^>]*>"
-syn match	iconInclude	"^\s*$\s*include\>\s*["<]" contains=iconIncluded
-"syn match iconLineSkip	"\\$"
-
-syn cluster	iconPreProcGroup contains=iconPreCondit,iconIncluded,iconInclude,iconDefine,iconInParen,iconUserLabel
-
-syn region	iconDefine	start="^\s*$\s*\(define\>\|undef\>\)" skip="\\$" end="$" contains=ALLBUT,@iconPreProcGroup
+" Comments {{{1
+syn keyword iconTodo	 TODO FIXME XXX BUG contained
+syn match   iconComment	 "#.*" contains=iconTodo,iconSpaceError,@Spell
+syn match   iconDocField "^#\s\+\zs\%(File\|Subject\|Authors\=\|Date\|Version\|Links\|Requires\|See also\):" contained
 
-"wt:syn region	iconPreProc "start="^\s*#\s*\(pragma\>\|line\>\|warning\>\|warn\>\|error\>\)" skip="\\$" "end="$" contains=ALLBUT,@iconPreProcGroup
-
-" Highlight User Labels
-
-" syn cluster	iconMultiGroup contains=iconIncluded,iconSpecial,iconTodo,iconUserCont,iconUserLabel,iconBitField
+if exists("icon_no_comment_fold")
+  syn region iconDocumentation	  start="\%^#\{2,}\%(\n#\+\%(\s\+.*\)\=\)\+"   end="^#\+\n\s*$"		  contains=iconDocField keepend
+else
+  syn region iconMultilineComment start="^\s*#.*\n\%(^\s*#\)\@=" end="^\s*#.*\n\%(^\s*#\)\@!" contains=iconComment  keepend fold transparent 
+  syn region iconDocumentation	  start="\%^#\{2,}\%(\n#\)\+"	 end="^#\+\n\%([^#]\|$\)"     contains=iconDocField keepend fold
+endif
 
+" Preprocessor {{{1
+syn match iconPreInclude  '^\s*\zs$\s*include\>\ze\s*"' nextgroup=iconIncluded skipwhite
+syn match iconIncluded '"[^"]\+"' contained
+
+syn region iconPreDefine      start="^\s*\zs$\s*\%(define\|undef\)\>"			     end="$" oneline contains=ALLBUT,@iconPreGroup
+syn region iconPreProc	      start="^\s*\zs$\s*\%(error\|line\)\>"			     end="$" oneline contains=ALLBUT,@iconPreGroup
+syn region iconPreConditional start="^\s*\zs$\s*\%(if\|ifdef\|ifndef\|elif\|else\|endif\)\>" end="$" oneline contains=iconComment,iconString,iconCset,iconNumber,iconSpaceError
+
+syn cluster iconPreGroup contains=iconPreCondit,iconPreInclude,iconIncluded,iconPreDefine
+
+syn match   iconPreSymbol "_V\d\+"
+syn keyword iconPreSymbol _ACORN _AMIGA _ARM_FUNCTIONS _ASCII _CALLING
+syn keyword iconPreSymbol _CO_EXPRESSIONS _COMPILED _DIRECT_EXECUTION
+syn keyword iconPreSymbol _DOS_FUNCTIONS _EBCDIC _EVENT_MONITOR
+syn keyword iconPreSymbol _EXECUTABLE_IMAGES _EXTERNAL_FUNCTIONS
+syn keyword iconPreSymbol _EXTERNAL_VALUES _INTERPRETED _KEYBOARD_FUNCTIONS
+syn keyword iconPreSymbol _LARGE_INTEGERS _MACINTOSH _MEMORY_MONITOR _MSDOS
+syn keyword iconPreSymbol _MSDOS_386 _MULTIREGION _MULTITASKING _OS2 _PIPES
+syn keyword iconPreSymbol _PORT _PRESENTATION_MGR _RECORD_IO _STRING_INVOKE
+syn keyword iconPreSymbol _SYSTEM_FUNCTION _UNIX _VISUALIZATION _VMS
+syn keyword iconPreSymbol _WINDOW_FUNCTIONS _X_WINDOW_SYSTEM 
+
+" Syncing {{{1
 if !exists("icon_minlines")
-  let icon_minlines = 15
+  let icon_minlines = 250
 endif
 exec "syn sync ccomment iconComment minlines=" . icon_minlines
 
-" Define the default highlighting.
-
-" Only when an item doesn't have highlighting
-
-" The default methods for highlighting.  Can be overridden later
+" Default Highlighting  {{{1
 
-" hi def link iconSpecialCharacter	iconSpecial
+hi def link iconParenError	iconError
+hi def link iconBracketError	iconError
+hi def link iconBraceError	iconError
+hi def link iconSpaceError	iconError
+hi def link iconError		Error
 
-hi def link iconOctalError		iconError
-hi def link iconParenError		iconError
-hi def link iconInParen		iconError
-hi def link iconCommentError	iconError
-hi def link iconSpaceError		iconError
-hi def link iconCommentError	iconError
-hi def link iconIncluded		iconString
-hi def link iconCommentString	iconString
-hi def link iconComment2String	iconString
-hi def link iconCommentSkip	iconComment
+hi def link iconInteger		Number
+hi def link iconReal		Float
+hi def link iconString		String
+hi def link iconCset		String
+hi def link iconStringSpecial	SpecialChar
 
-hi def link iconUserLabel		Label
-hi def link iconCharacter		Character
-hi def link iconNumber			Number
-hi def link iconRadix			Number
-hi def link iconFloat			Float
-hi def link iconInclude		Include
 hi def link iconPreProc		PreProc
-hi def link iconDefine			Macro
-hi def link iconError			Error
-hi def link iconStatement		Statement
-hi def link iconPreCondit		PreCondit
-hi def link iconString			String
-hi def link iconCset			String
-hi def link iconComment		Comment
-hi def link iconSpecial		SpecialChar
-hi def link iconTodo			Todo
-hi def link iconStorageClass	StorageClass
-hi def link iconFunction		Statement
-hi def link iconReserved		Label
-hi def link iconKeyword		Operator
+hi def link iconIncluded	iconString
+hi def link iconPreInclude	Include
+hi def link iconPreSymbol	iconPreProc
+hi def link iconPreDefine	Define
+hi def link iconPreConditional	PreCondit
 
-"hi def link iconIdentifier	Identifier
+hi def link iconStatement	Statement
+hi def link iconStorageClass	StorageClass
+hi def link iconFunction	Function
+hi def link iconReserved	Label
+hi def link iconLink		Include
+hi def link iconKeyword		Keyword
 
+hi def link iconComment		Comment
+hi def link iconTodo		Todo
+hi def link iconDocField	SpecialComment
+hi def link iconDocumentation	Comment
 
+" Postscript  {{{1
 let b:current_syntax = "icon"
 
+" vim: nowrap sw=2 sts=2 ts=8 noet fdm=marker:
diff --git a/runtime/syntax/initng.vim b/runtime/syntax/initng.vim
index 5d7685cde1..959c79a176 100644
--- a/runtime/syntax/initng.vim
+++ b/runtime/syntax/initng.vim
@@ -20,7 +20,6 @@ endif
 syn case match
 
 let is_bash = 1
-unlet! b:current_syntax
 syn include @shTop syntax/sh.vim
 
 syn region	initngService			matchgroup=initngServiceHeader start="^\s*\(service\|virtual\|daemon\|class\|cron\)\s\+\(\(\w\|[-/*]\)\+\(\s\+:\s\+\(\w\|[-/*]\)\+\)\?\)\s\+{" end="}" contains=@initngServiceCluster
diff --git a/runtime/syntax/ipfilter.vim b/runtime/syntax/ipfilter.vim
index a7b7df2bac..c00762623f 100644
--- a/runtime/syntax/ipfilter.vim
+++ b/runtime/syntax/ipfilter.vim
@@ -1,7 +1,7 @@
 " ipfilter syntax file
 " Language: ipfilter configuration file
 " Maintainer: Hendrik Scholz <hendrik@scholz.net>
-" Last Change: 2005 Jan 27
+" Last Change: 2022 Jun 14
 "
 " http://www.wormulon.net/files/misc/ipfilter.vim
 "
@@ -52,3 +52,4 @@ hi def link IPFNetmask	String
 hi def link IPFAny		Statement
 hi def link IPFProto	Identifier
 
+let b:current_syntax = 'ipfilter'
diff --git a/runtime/syntax/mupad.vim b/runtime/syntax/mupad.vim
index 55ea9c4e43..df87ad14fe 100644
--- a/runtime/syntax/mupad.vim
+++ b/runtime/syntax/mupad.vim
@@ -279,5 +279,6 @@ hi def link mupadType		Type
 hi def link mupadDefine		Define
 hi def link mupadIdentifier	Identifier
 
+let b:current_syntax = 'mupad'
 
 " TODO  More comprehensive listing.
diff --git a/runtime/syntax/perl.vim b/runtime/syntax/perl.vim
index 59611b66a4..73f967a183 100644
--- a/runtime/syntax/perl.vim
+++ b/runtime/syntax/perl.vim
@@ -4,7 +4,7 @@
 " Homepage:      https://github.com/vim-perl/vim-perl
 " Bugs/requests: https://github.com/vim-perl/vim-perl/issues
 " License:       Vim License (see :help license)
-" Last Change:   2021 Oct 7
+" Last Change:   2022 Jun 13
 " Contributors:  Andy Lester <andy@petdance.com>
 "                Hinrik Örn Sigurðsson <hinrik.sig@gmail.com>
 "                Lukas Mai <l.mai.web.de>
@@ -442,11 +442,18 @@ syn match  perlFormatField	"@$" contained
 " This problem also exists with empty string delimited heredocs but there's no
 " known workaround for that case.
 if get(g:, 'perl_fold', 0)
-  syntax region perlDATA matchgroup=perlDATAStart start="^__DATA__$" end="VIM_PERL_EOF\%$" contains=perlPOD,@perlDATA fold
-  syntax region perlEND  matchgroup=perlENDStart  start="^__END__$"  end="VIM_PERL_EOF\%$" contains=perlPOD,@perlDATA fold
+  syntax region perlDATA matchgroup=perlDATAStart start="^__DATA__$" end="VIM_PERL_EOF\%$" contains=@perlDATA fold
+  syntax region perlEND  matchgroup=perlENDStart  start="^__END__$"  end="VIM_PERL_EOF\%$" contains=@perlDATA fold
 else
-  syntax region perlDATA matchgroup=perlDATAStart start="^__DATA__$" end="\%$" contains=perlPOD,@perlDATA
-  syntax region perlEND  matchgroup=perlENDStart  start="^__END__$"  end="\%$" contains=perlPOD,@perlDATA
+  syntax region perlDATA matchgroup=perlDATAStart start="^__DATA__$" end="\%$" contains=@perlDATA
+  syntax region perlEND  matchgroup=perlENDStart  start="^__END__$"  end="\%$" contains=@perlDATA
+endif
+
+" TODO: generalise this to allow other filetypes
+if get(g:, 'perl_highlight_data', 0)
+  syn cluster perlDATA add=perlPOD
+else
+  syn cluster perlDATA remove=perlPOD
 endif
 
 "
diff --git a/runtime/syntax/pod.vim b/runtime/syntax/pod.vim
index 44439cb2cd..90c9b99a3e 100644
--- a/runtime/syntax/pod.vim
+++ b/runtime/syntax/pod.vim
@@ -5,7 +5,7 @@
 " Homepage:      https://github.com/vim-perl/vim-perl
 " Bugs/requests: https://github.com/vim-perl/vim-perl/issues
 " License:       Vim License (see :help license)
-" Last Change:   2021 Oct 8
+" Last Change:   2022 Jun 13
 
 " To add embedded POD documentation highlighting to your syntax file, add
 " the commands:
diff --git a/runtime/syntax/sendpr.vim b/runtime/syntax/sendpr.vim
index 2e07802047..2541b95c67 100644
--- a/runtime/syntax/sendpr.vim
+++ b/runtime/syntax/sendpr.vim
@@ -1,7 +1,7 @@
 " Vim syntax file
 " Language: FreeBSD send-pr file
 " Maintainer: Hendrik Scholz <hendrik@scholz.net>
-" Last Change: 2012 Feb 03
+" Last Change: 2022 Jun 14
 "
 " http://raisdorf.net/files/misc/send-pr.vim
 
@@ -31,5 +31,7 @@ hi def link sendprType      Type
 hi def link sendprString    String
 hi def link sendprLabel     Label
 
+let b:current_syntax = 'sendpr'
+
 let &cpo = s:cpo_save
 unlet s:cpo_save
diff --git a/runtime/syntax/tar.vim b/runtime/syntax/tar.vim
index 497683a186..815c2219cb 100644
--- a/runtime/syntax/tar.vim
+++ b/runtime/syntax/tar.vim
@@ -14,4 +14,6 @@ hi def link tarComment	Comment
 hi def link tarFilename	Constant
 hi def link tarDirectory Type
 
+let b:current_syntax = 'tar'
+
 " vim: ts=8
diff --git a/runtime/syntax/trustees.vim b/runtime/syntax/trustees.vim
index 6c58d3983d..3a7d26e896 100644
--- a/runtime/syntax/trustees.vim
+++ b/runtime/syntax/trustees.vim
@@ -1,7 +1,7 @@
 " Vim syntax file
 " Language:     trustees
 " Maintainer:   Nima Talebi <nima@it.net.au>
-" Last Change:  2005-10-12
+" Last Change:  2022 Jun 14
 
 " quit when a syntax file was already loaded
 if exists("b:current_syntax")
@@ -40,3 +40,5 @@ syntax match tfsRuleWho ~\(\*\|[+]\{0,1\}[a-zA-Z0-9/]\+\)~ contained contains=tf
 highlight link tfsRuleWho Identifier
 syntax match tfsRuleWhat ~[RWEBXODCU!]\+~ contained contains=tfsSpecialChar
 highlight link tfsRuleWhat Structure
+
+let b:current_syntax = 'trustees'
diff --git a/runtime/syntax/vim.vim b/runtime/syntax/vim.vim
index 0eec9f13de..9917a7f694 100644
--- a/runtime/syntax/vim.vim
+++ b/runtime/syntax/vim.vim
@@ -435,8 +435,8 @@ syn case match
 " User Function Highlighting: {{{2
 " (following Gautam Iyer's suggestion)
 " ==========================
-syn match vimFunc		"\%(\%([sSgGbBwWtTlL]:\|<[sS][iI][dD]>\)\=\%(\w\+\.\)*\I[a-zA-Z0-9_.]*\)\ze\s*("		contains=vimCommand,vimFuncEcho,vimFuncName,vimUserFunc,vimExecute
-syn match vimUserFunc contained	"\%(\%([sSgGbBwWtTlL]:\|<[sS][iI][dD]>\)\=\%(\w\+\.\)*\I[a-zA-Z0-9_.]*\)\|\<\u[a-zA-Z0-9.]*\>\|\<if\>"	contains=vimCommand,vimNotation
+syn match vimFunc		"\%(\%([sSgGbBwWtTlL]:\|<[sS][iI][dD]>\)\=\%(\w\+\.\)*\I[a-zA-Z0-9_.]*\)\ze\s*("		contains=vimFuncEcho,vimFuncName,vimUserFunc,vimExecute
+syn match vimUserFunc contained	"\%(\%([sSgGbBwWtTlL]:\|<[sS][iI][dD]>\)\=\%(\w\+\.\)*\I[a-zA-Z0-9_.]*\)\|\<\u[a-zA-Z0-9.]*\>\|\<if\>"	contains=vimNotation
 syn keyword vimFuncEcho contained	ec ech echo
 
 " User Command Highlighting: {{{2