25 files changed, 635 insertions, 166 deletions
diff --git a/runtime/autoload/python.vim b/runtime/autoload/python.vim
index 1eaad09ef5..d5f4862363 100644
--- a/runtime/autoload/python.vim
+++ b/runtime/autoload/python.vim
@@ -22,8 +22,7 @@ let s:maxoff = 50       " maximum number of lines to look backwards for ()
 function s:SearchBracket(fromlnum, flags)
   return searchpairpos('[[({]', '', '[])}]', a:flags,
           \ {-> synstack('.', col('.'))
-          \   ->map({_, id -> id->synIDattr('name')})
-          \   ->match('\%(Comment\|Todo\|String\)$') >= 0},
+          \ ->indexof({_, id -> synIDattr(id, 'name') =~ '\%(Comment\|Todo\|String\)$'}) >= 0},
           \ [0, a:fromlnum - s:maxoff]->max(), g:python_indent.searchpair_timeout)
 endfunction
 
@@ -157,15 +156,13 @@ function python#GetIndent(lnum, ...)
     " the start of the comment.  synID() is slow, a linear search would take
     " too long on a long line.
     if synstack(plnum, pline_len)
-    \ ->map({_, id -> id->synIDattr('name')})
-    \ ->match('\%(Comment\|Todo\)$') >= 0
+    \ ->indexof({_, id -> synIDattr(id, 'name') =~ '\%(Comment\|Todo\)$'}) >= 0
       let min = 1
       let max = pline_len
       while min < max
 	let col = (min + max) / 2
         if synstack(plnum, col)
-        \ ->map({_, id -> id->synIDattr('name')})
-        \ ->match('\%(Comment\|Todo\)$') >= 0
+        \ ->indexof({_, id -> synIDattr(id, 'name') =~ '\%(Comment\|Todo\)$'}) >= 0
 	  let max = col
 	else
 	  let min = col + 1
diff --git a/runtime/doc/builtin.txt b/runtime/doc/builtin.txt
index 3ff4e47a45..b74e30db09 100644
--- a/runtime/doc/builtin.txt
+++ b/runtime/doc/builtin.txt
@@ -2126,8 +2126,7 @@ extend({expr1}, {expr2} [, {expr3}])			*extend()*
 extendnew({expr1}, {expr2} [, {expr3}])			*extendnew()*
 		Like |extend()| but instead of adding items to {expr1} a new
 		List or Dictionary is created and returned.  {expr1} remains
-		unchanged.  Items can still be changed by {expr2}, if you
-		don't want that use |deepcopy()| first.
+		unchanged.
 
 
 feedkeys({string} [, {mode}])				*feedkeys()*
@@ -8725,6 +8724,8 @@ timer_start({time}, {callback} [, {options}])
 		{time} is the waiting time in milliseconds. This is the
 		minimum time before invoking the callback.  When the system is
 		busy or Vim is not waiting for input the time will be longer.
+		Zero can be used to execute the callback when Vim is back in
+		the main loop.
 
 		{callback} is the function to call.  It can be the name of a
 		function or a |Funcref|.  It is called with one argument, which
diff --git a/runtime/doc/change.txt b/runtime/doc/change.txt
index 990ba3d8fd..2cebd8abdd 100644
--- a/runtime/doc/change.txt
+++ b/runtime/doc/change.txt
@@ -276,7 +276,9 @@ gr{char}		Replace the virtual characters under the cursor with
 			{char}.  This replaces in screen space, not file
 			space.  See |gR| and |Virtual-Replace-mode| for more
 			details.  As with |r| a count may be given.
-			{char} can be entered like with |r|.
+			{char} can be entered like with |r|, but characters
+			that have a special meaning in Insert mode, such as
+			most CTRL-keys, cannot be used.
 
 						*digraph-arg*
 The argument for Normal mode commands like |r| and |t| is a single character.
@@ -976,7 +978,7 @@ inside of strings can change!  Also see 'softtabstop' option. >
 <			to display registers '1' and 'a'.  Spaces are allowed
 			in {arg}.
 
-							*:di* *:display*
+							*:di* *:dis* *:display*
 :di[splay] [arg]	Same as :registers.
 
 							*y* *yank*
diff --git a/runtime/doc/map.txt b/runtime/doc/map.txt
index ad0570e9f7..3a5223fa3a 100644
--- a/runtime/doc/map.txt
+++ b/runtime/doc/map.txt
@@ -1205,12 +1205,14 @@ functions used in one script use the same name as in other scripts.  To avoid
 this, they can be made local to the script.
 
 						*<SID>* *<SNR>* *E81*
-The string "<SID>" can be used in a mapping or menu.
+The string "<SID>" can be used in a mapping or menu.  This is useful if you
+have a script-local function that you want to call from a mapping in the same
+script.
    When executing the map command, Vim will replace "<SID>" with the special
 key code <SNR>, followed by a number that's unique for the script, and an
 underscore.  Example: >
 	:map <SID>Add
-could define a mapping "<SNR>23_Add".
+would define a mapping "<SNR>23_Add".
 
 When defining a function in a script, "s:" can be prepended to the name to
 make it local to the script.  But when a mapping is executed from outside of
diff --git a/runtime/doc/sign.txt b/runtime/doc/sign.txt
index 53ef03eb63..162bdaed7b 100644
--- a/runtime/doc/sign.txt
+++ b/runtime/doc/sign.txt
@@ -595,23 +595,23 @@ sign_placelist({list})
 		|sign_place()| function.  The {list} argument specifies the
 		List of signs to place. Each list item is a dict with the
 		following sign attributes:
-		    buffer	buffer name or number. For the accepted
+		    buffer	Buffer name or number. For the accepted
 				values, see |bufname()|.
-		    group	sign group. {group} functions as a namespace
+		    group	Sign group. {group} functions as a namespace
 				for {id}, thus two groups can use the same
 				IDs. If not specified or set to an empty
 				string, then the global group is used.   See
 				|sign-group| for more information.
-		    id		sign identifier. If not specified or zero,
+		    id		Sign identifier. If not specified or zero,
 				then a new unique identifier is allocated.
 				Otherwise the specified number is used. See
 				|sign-identifier| for more information.
-		    lnum	line number in the buffer where the sign is to
+		    lnum	Line number in the buffer where the sign is to
 				be placed. For the accepted values, see
 				|line()|.
-		    name	name of the sign to place. See |sign_define()|
+		    name	Name of the sign to place. See |sign_define()|
 				for more information.
-		    priority	priority of the sign. When multiple signs are
+		    priority	Priority of the sign. When multiple signs are
 				placed on a line, the sign with the highest
 				priority is used. If not specified, the
 				default value of 10 is used. See
diff --git a/runtime/doc/syntax.txt b/runtime/doc/syntax.txt
index 7102e93f0a..68d059be82 100644
--- a/runtime/doc/syntax.txt
+++ b/runtime/doc/syntax.txt
@@ -2756,17 +2756,25 @@ For highlighted doctests and code inside: >
 	:let python_no_doctest_highlight = 1
 or >
 	:let python_no_doctest_code_highlight = 1
-(first option implies second one).
+The first option implies the second one.
 
 For highlighted trailing whitespace and mix of spaces and tabs: >
 	:let python_space_error_highlight = 1
 
-If you want all possible Python highlighting (the same as setting the
-preceding last option and unsetting all other ones): >
+If you want all possible Python highlighting: >
 	:let python_highlight_all = 1
+This has the same effect as setting python_space_error_highlight and
+unsetting all the other ones.
+
+If you use Python 2 or straddling code (Python 2 and 3 compatible),
+you can enforce the use of an older syntax file with support for
+Python 2 and up to Python 3.5.  >
+	: let python_use_python2_syntax = 1
+This option will exclude all modern Python 3.6 or higher features.
+
+Note: Only existence of these options matters, not their value.
+      You can replace 1 above with anything.
 
-Note: Only existence of these options matter, not their value. You can replace
-      1 above with anything.
 
 QUAKE						*quake.vim* *ft-quake-syntax*
 
@@ -5179,7 +5187,7 @@ Conceal		Placeholder characters substituted for concealed
 							*hl-CurSearch*
 CurSearch	Used for highlighting a search pattern under the cursor
 		(see 'hlsearch').
-							*hl-Cursor*
+						*hl-Cursor* *hl-lCursor*
 Cursor		Character under the cursor.
 lCursor		Character under the cursor when |language-mapping|
 		is used (see 'guicursor').
diff --git a/runtime/ftplugin/quarto.vim b/runtime/ftplugin/quarto.vim
new file mode 100644
index 0000000000..a76bcc2c7e
--- /dev/null
+++ b/runtime/ftplugin/quarto.vim
@@ -0,0 +1 @@
+runtime ftplugin/rmd.vim
diff --git a/runtime/ftplugin/r.vim b/runtime/ftplugin/r.vim
index a78afa2e7e..28966368cb 100644
--- a/runtime/ftplugin/r.vim
+++ b/runtime/ftplugin/r.vim
@@ -2,7 +2,7 @@
 " Language: R
 " Maintainer: Jakson Alves de Aquino <jalvesaq@gmail.com>
 " Homepage: https://github.com/jalvesaq/R-Vim-runtime
-" Last Change:	Sat Aug 15, 2020  11:37AM
+" Last Change:	Sun Apr 24, 2022  09:14AM
 
 " Only do this when not yet done for this buffer
 if exists("b:did_ftplugin")
@@ -22,7 +22,7 @@ setlocal comments=:#',:###,:##,:#
 
 if (has("gui_win32") || has("gui_gtk")) && !exists("b:browsefilter")
   let b:browsefilter = "R Source Files (*.R)\t*.R\n" .
-        \ "Files that include R (*.Rnw *.Rd *.Rmd *.Rrst)\t*.Rnw;*.Rd;*.Rmd;*.Rrst\n" .
+        \ "Files that include R (*.Rnw *.Rd *.Rmd *.Rrst *.qmd)\t*.Rnw;*.Rd;*.Rmd;*.Rrst;*.qmd\n" .
         \ "All Files (*.*)\t*.*\n"
 endif
 
diff --git a/runtime/ftplugin/rhelp.vim b/runtime/ftplugin/rhelp.vim
index d0b546d62d..2fde4875c6 100644
--- a/runtime/ftplugin/rhelp.vim
+++ b/runtime/ftplugin/rhelp.vim
@@ -2,7 +2,7 @@
 " Language: R help file
 " Maintainer: Jakson Alves de Aquino <jalvesaq@gmail.com>
 " Homepage: https://github.com/jalvesaq/R-Vim-runtime
-" Last Change:	Sat Aug 15, 2020  12:01PM
+" Last Change:	Sun Apr 24, 2022  09:12AM
 
 " Only do this when not yet done for this buffer
 if exists("b:did_ftplugin")
@@ -18,7 +18,7 @@ set cpo&vim
 setlocal iskeyword=@,48-57,_,.
 
 if (has("gui_win32") || has("gui_gtk")) && !exists("b:browsefilter")
-  let b:browsefilter = "R Source Files (*.R *.Rnw *.Rd *.Rmd *.Rrst)\t*.R;*.Rnw;*.Rd;*.Rmd;*.Rrst\n" .
+  let b:browsefilter = "R Source Files (*.R *.Rnw *.Rd *.Rmd *.Rrst *.qmd)\t*.R;*.Rnw;*.Rd;*.Rmd;*.Rrst;*.qmd\n" .
         \ "All Files (*.*)\t*.*\n"
 endif
 
diff --git a/runtime/ftplugin/rmd.vim b/runtime/ftplugin/rmd.vim
index 2ee72ffc6c..355b88f04a 100644
--- a/runtime/ftplugin/rmd.vim
+++ b/runtime/ftplugin/rmd.vim
@@ -2,7 +2,7 @@
 " Language: R Markdown file
 " Maintainer: Jakson Alves de Aquino <jalvesaq@gmail.com>
 " Homepage: https://github.com/jalvesaq/R-Vim-runtime
-" Last Change:	Sat Aug 15, 2020  12:03PM
+" Last Change:	Sun Apr 24, 2022  09:12AM
 " Original work by Alex Zvoleff (adjusted from R help for rmd by Michel Kuhlmann)
 
 " Only do this when not yet done for this buffer
@@ -32,13 +32,24 @@ function! FormatRmd()
   return 1
 endfunction
 
-" If you do not want 'comments' dynamically defined, put in your vimrc:
-" let g:rmd_dynamic_comments = 0
+function! SetRmdCommentStr()
+    if (search("^[ \t]*```[ ]*{r", "bncW") > search("^[ \t]*```$", "bncW")) || ((search('^---$', 'Wn') || search('^\.\.\.$', 'Wn')) && search('^---$', 'bnW'))
+        set commentstring=#\ %s
+    else
+        set commentstring=<!--\ %s\ -->
+    endif
+endfunction
+
+" If you do not want both 'comments' and 'commentstring' dynamically defined,
+" put in your vimrc: let g:rmd_dynamic_comments = 0
 if !exists("g:rmd_dynamic_comments") || (exists("g:rmd_dynamic_comments") && g:rmd_dynamic_comments == 1)
   setlocal formatexpr=FormatRmd()
+  augroup RmdCStr
+    autocmd!
+    autocmd CursorMoved <buffer> call SetRmdCommentStr()
+  augroup END
 endif
 
-
 " Enables pandoc if it is installed
 unlet! b:did_ftplugin
 runtime ftplugin/pandoc.vim
@@ -47,7 +58,7 @@ runtime ftplugin/pandoc.vim
 let b:did_ftplugin = 1
 
 if (has("gui_win32") || has("gui_gtk")) && !exists("b:browsefilter")
-  let b:browsefilter = "R Source Files (*.R *.Rnw *.Rd *.Rmd *.Rrst)\t*.R;*.Rnw;*.Rd;*.Rmd;*.Rrst\n" .
+  let b:browsefilter = "R Source Files (*.R *.Rnw *.Rd *.Rmd *.Rrst *.qmd)\t*.R;*.Rnw;*.Rd;*.Rmd;*.Rrst;*.qmd\n" .
         \ "All Files (*.*)\t*.*\n"
 endif
 
diff --git a/runtime/ftplugin/rnoweb.vim b/runtime/ftplugin/rnoweb.vim
index dc5f1b5e06..cf1c0922c0 100644
--- a/runtime/ftplugin/rnoweb.vim
+++ b/runtime/ftplugin/rnoweb.vim
@@ -2,7 +2,7 @@
 " Language: Rnoweb
 " Maintainer: Jakson Alves de Aquino <jalvesaq@gmail.com>
 " Homepage: https://github.com/jalvesaq/R-Vim-runtime
-" Last Change:	Sat Aug 15, 2020  12:02PM
+" Last Change:	Sun Apr 24, 2022  09:13AM
 
 " Only do this when not yet done for this buffer
 if exists("b:did_ftplugin")
@@ -25,10 +25,27 @@ setlocal suffixesadd=.bib,.tex
 setlocal comments=b:%,b:#,b:##,b:###,b:#'
 
 if (has("gui_win32") || has("gui_gtk")) && !exists("b:browsefilter")
-  let b:browsefilter = "R Source Files (*.R *.Rnw *.Rd *.Rmd *.Rrst)\t*.R;*.Rnw;*.Rd;*.Rmd;*.Rrst\n" .
+  let b:browsefilter = "R Source Files (*.R *.Rnw *.Rd *.Rmd *.Rrst *.qmd)\t*.R;*.Rnw;*.Rd;*.Rmd;*.Rrst;*.qmd\n" .
         \ "All Files (*.*)\t*.*\n"
 endif
 
+function! SetRnwCommentStr()
+    if (search("^\s*<<.*>>=", "bncW") > search("^@", "bncW"))
+        set commentstring=#\ %s
+    else
+        set commentstring=%\ %s
+    endif
+endfunction
+
+" If you do not want both 'comments' and 'commentstring' dynamically defined,
+" put in your vimrc: let g:rnw_dynamic_comments = 0
+if !exists("g:rnw_dynamic_comments") || (exists("g:rnw_dynamic_comments") && g:rnw_dynamic_comments == 1)
+  augroup RnwCStr
+    autocmd!
+    autocmd CursorMoved <buffer> call SetRnwCommentStr()
+  augroup END
+endif
+
 if exists('b:undo_ftplugin')
   let b:undo_ftplugin .= " | setl isk< sua< com< | unlet! b:browsefilter"
 else
diff --git a/runtime/ftplugin/rrst.vim b/runtime/ftplugin/rrst.vim
index a56fd6478e..19c67c4cc2 100644
--- a/runtime/ftplugin/rrst.vim
+++ b/runtime/ftplugin/rrst.vim
@@ -2,7 +2,7 @@
 " Language: reStructuredText documentation format with R code
 " Maintainer: Jakson Alves de Aquino <jalvesaq@gmail.com>
 " Homepage: https://github.com/jalvesaq/R-Vim-runtime
-" Last Change:	Sat Aug 15, 2020  12:02PM
+" Last Change:	Sun Apr 24, 2022  09:13AM
 " Original work by Alex Zvoleff
 
 " Only do this when not yet done for this buffer
@@ -38,7 +38,7 @@ if !exists("g:rrst_dynamic_comments") || (exists("g:rrst_dynamic_comments") && g
 endif
 
 if (has("gui_win32") || has("gui_gtk")) && !exists("b:browsefilter")
-  let b:browsefilter = "R Source Files (*.R *.Rnw *.Rd *.Rmd *.Rrst)\t*.R;*.Rnw;*.Rd;*.Rmd;*.Rrst\n" .
+  let b:browsefilter = "R Source Files (*.R *.Rnw *.Rd *.Rmd *.Rrst *.qmd)\t*.R;*.Rnw;*.Rd;*.Rmd;*.Rrst;*.qmd\n" .
         \ "All Files (*.*)\t*.*\n"
 endif
 
diff --git a/runtime/indent/quarto.vim b/runtime/indent/quarto.vim
new file mode 100644
index 0000000000..586d232d2b
--- /dev/null
+++ b/runtime/indent/quarto.vim
@@ -0,0 +1 @@
+runtime indent/rmd.vim
diff --git a/runtime/indent/r.vim b/runtime/indent/r.vim
index ca85a2e62d..293dd98175 100644
--- a/runtime/indent/r.vim
+++ b/runtime/indent/r.vim
@@ -2,7 +2,7 @@
 " Language:	R
 " Author:	Jakson Alves de Aquino <jalvesaq@gmail.com>
 " Homepage:     https://github.com/jalvesaq/R-Vim-runtime
-" Last Change:	Sun Aug 19, 2018  09:13PM
+" Last Change:	Wed Oct 26, 2022  12:04PM
 
 
 " Only load this indent file when no other was loaded.
@@ -14,6 +14,8 @@ let b:did_indent = 1
 setlocal indentkeys=0{,0},:,!^F,o,O,e
 setlocal indentexpr=GetRIndent()
 
+let b:undo_indent = "setl inde< indk<"
+
 " Only define the function once.
 if exists("*GetRIndent")
   finish
@@ -28,7 +30,7 @@ let g:r_indent_ess_comments   = get(g:, 'r_indent_ess_comments',    0)
 let g:r_indent_comment_column = get(g:, 'r_indent_comment_column', 40)
 let g:r_indent_ess_compatible = get(g:, 'r_indent_ess_compatible',  0)
 let g:r_indent_op_pattern     = get(g:, 'r_indent_op_pattern',
-      \ '\(&\||\|+\|-\|\*\|/\|=\|\~\|%\|->\)\s*$')
+      \ '\(&\||\|+\|-\|\*\|/\|=\|\~\|%\|->\||>\)\s*$')
 
 function s:RDelete_quotes(line)
   let i = 0
@@ -359,17 +361,19 @@ function GetRIndent()
   let olnum = s:Get_prev_line(lnum)
   let oline = getline(olnum)
   if olnum > 0
-    if line =~ g:r_indent_op_pattern && s:Get_paren_balance(line, "(", ")") == 0
-      if oline =~ g:r_indent_op_pattern && s:Get_paren_balance(line, "(", ")") == 0
+    if substitute(line, '#.*', '', '') =~ g:r_indent_op_pattern && s:Get_paren_balance(line, "(", ")") == 0
+      if substitute(oline, '#.*', '', '') =~ g:r_indent_op_pattern && s:Get_paren_balance(line, "(", ")") == 0
         return indent(lnum)
       else
         return indent(lnum) + shiftwidth()
       endif
     else
-      if oline =~ g:r_indent_op_pattern && s:Get_paren_balance(line, "(", ")") == 0
+      if substitute(oline, '#.*', '', '') =~ g:r_indent_op_pattern && s:Get_paren_balance(line, "(", ")") == 0
         return indent(lnum) - shiftwidth()
       endif
     endif
+  elseif substitute(line, '#.*', '', '') =~ g:r_indent_op_pattern && s:Get_paren_balance(line, "(", ")") == 0
+    return indent(lnum) + shiftwidth()
   endif
 
   let post_fun = 0
diff --git a/runtime/indent/rhelp.vim b/runtime/indent/rhelp.vim
index cf69ae3392..2b9d49b915 100644
--- a/runtime/indent/rhelp.vim
+++ b/runtime/indent/rhelp.vim
@@ -2,7 +2,7 @@
 " Language:	R Documentation (Help), *.Rd
 " Author:	Jakson Alves de Aquino <jalvesaq@gmail.com>
 " Homepage:     https://github.com/jalvesaq/R-Vim-runtime
-" Last Change:	Tue Apr 07, 2015  04:38PM
+" Last Change:	Feb 25, 2023
 
 
 " Only load this indent file when no other was loaded.
@@ -20,6 +20,8 @@ setlocal nolisp
 setlocal indentkeys=0{,0},:,!^F,o,O,e
 setlocal indentexpr=GetCorrectRHelpIndent()
 
+let b:undo_indent = "setl ai< cin< inde< indk< lisp< si<"
+
 " Only define the functions once.
 if exists("*GetRHelpIndent")
   finish
diff --git a/runtime/indent/rmd.vim b/runtime/indent/rmd.vim
index 8fd57257fa..a043b0c994 100644
--- a/runtime/indent/rmd.vim
+++ b/runtime/indent/rmd.vim
@@ -2,7 +2,7 @@
 " Language:	Rmd
 " Author:	Jakson Alves de Aquino <jalvesaq@gmail.com>
 " Homepage:     https://github.com/jalvesaq/R-Vim-runtime
-" Last Change:	Sun Mar 28, 2021  08:05PM
+" Last Change:	Wed Nov 09, 2022  09:44PM
 
 
 " Only load this indent file when no other was loaded.
@@ -16,6 +16,8 @@ let b:did_indent = 1
 setlocal indentkeys=0{,0},<:>,!^F,o,O,e
 setlocal indentexpr=GetRmdIndent()
 
+let b:undo_indent = "setl inde< indk<"
+
 if exists("*GetRmdIndent")
   finish
 endif
@@ -47,6 +49,8 @@ function s:GetMdIndent()
     return indent(v:lnum - 1) + 2
   elseif pline =~ '^\s*\d\+\.\s\+'
     return indent(v:lnum - 1) + 3
+  elseif pline =~ '^\[\^\S\+\]: '
+    return indent(v:lnum - 1) + shiftwidth()
   endif
   return indent(prevnonblank(v:lnum - 1))
 endfunction
diff --git a/runtime/indent/rnoweb.vim b/runtime/indent/rnoweb.vim
index 73966868b8..33bc103d18 100644
--- a/runtime/indent/rnoweb.vim
+++ b/runtime/indent/rnoweb.vim
@@ -2,7 +2,7 @@
 " Language:	Rnoweb
 " Author:	Jakson Alves de Aquino <jalvesaq@gmail.com>
 " Homepage:     https://github.com/jalvesaq/R-Vim-runtime
-" Last Change:	Fri Apr 15, 2016  10:58PM
+" Last Change:	Feb 25, 2023
 
 
 " Only load this indent file when no other was loaded.
@@ -29,6 +29,8 @@ let b:did_indent = 1
 setlocal indentkeys=0{,0},!^F,o,O,e,},=\bibitem,=\item
 setlocal indentexpr=GetRnowebIndent()
 
+let b:undo_indent = "setl inde< indk<"
+
 if exists("*GetRnowebIndent")
   finish
 endif
diff --git a/runtime/indent/rrst.vim b/runtime/indent/rrst.vim
index f3ee53e7fb..585c5e6654 100644
--- a/runtime/indent/rrst.vim
+++ b/runtime/indent/rrst.vim
@@ -2,7 +2,7 @@
 " Language:	Rrst
 " Author:	Jakson Alves de Aquino <jalvesaq@gmail.com>
 " Homepage:     https://github.com/jalvesaq/R-Vim-runtime
-" Last Change:	Tue Apr 07, 2015  04:38PM
+" Last Change:	Feb 25, 2023
 
 
 " Only load this indent file when no other was loaded.
@@ -16,6 +16,8 @@ let b:did_indent = 1
 setlocal indentkeys=0{,0},:,!^F,o,O,e
 setlocal indentexpr=GetRrstIndent()
 
+let b:undo_indent = "setl inde< indk<"
+
 if exists("*GetRrstIndent")
   finish
 endif
diff --git a/runtime/plugin/matchparen.vim b/runtime/plugin/matchparen.vim
index 3982489b92..e19b283228 100644
--- a/runtime/plugin/matchparen.vim
+++ b/runtime/plugin/matchparen.vim
@@ -108,8 +108,9 @@ func s:Highlight_Matching_Pair()
     " searchpairpos()'s skip argument.
     " We match "escape" for special items, such as lispEscapeSpecial, and
     " match "symbol" for lispBarSymbol.
-    let s_skip = '!empty(filter(map(synstack(line("."), col(".")), ''synIDattr(v:val, "name")''), ' .
-	\ '''v:val =~? "string\\|character\\|singlequote\\|escape\\|symbol\\|comment"''))'
+    let s_skip = 'synstack(".", col("."))'
+        \ . '->indexof({_, id -> synIDattr(id, "name") =~? '
+        \ . '"string\\|character\\|singlequote\\|escape\\|symbol\\|comment"}) >= 0'
     " If executing the expression determines that the cursor is currently in
     " one of the syntax types, then we want searchpairpos() to find the pair
     " within those syntax types (i.e., not skip).  Otherwise, the cursor is
diff --git a/runtime/syntax/python.vim b/runtime/syntax/python.vim
index ef4da1b448..831fb92f4c 100644
--- a/runtime/syntax/python.vim
+++ b/runtime/syntax/python.vim
@@ -1,7 +1,7 @@
 " Vim syntax file
 " Language:	Python
 " Maintainer:	Zvezdan Petkovic <zpetkovic@acm.org>
-" Last Change:	2022 Jun 28
+" Last Change:	2023 Feb 26
 " Credits:	Neil Schemenauer <nas@python.ca>
 "		Dmitry Vasiliev
 "
@@ -35,12 +35,26 @@
 "
 "   let python_highlight_all = 1
 "
+" The use of Python 2 compatible syntax highlighting can be enforced.
+" The straddling code (Python 2 and 3 compatible), up to Python 3.5,
+" will be also supported.
+"
+"   let python_use_python2_syntax = 1
+"
+" This option will exclude all modern Python 3.6 or higher features.
+"
 
 " quit when a syntax file was already loaded.
 if exists("b:current_syntax")
   finish
 endif
 
+" Use of Python 2 and 3.5 or lower requested.
+if exists("python_use_python2_syntax")
+  runtime! syntax/python2.vim
+  finish
+endif
+
 " We need nocompatible mode in order to continue lines with backslashes.
 " Original setting will be restored.
 let s:cpo_save = &cpo
@@ -91,8 +105,8 @@ syn keyword pythonInclude	from import
 syn keyword pythonAsync		async await
 
 " Soft keywords
-" These keywords do not mean anything unless used in the right context
-" See https://docs.python.org/3/reference/lexical_analysis.html#soft-keywords 
+" These keywords do not mean anything unless used in the right context.
+" See https://docs.python.org/3/reference/lexical_analysis.html#soft-keywords
 " for more on this.
 syn match   pythonConditional   "^\s*\zscase\%(\s\+.*:.*$\)\@="
 syn match   pythonConditional   "^\s*\zsmatch\%(\s\+.*:\s*\%(#.*\)\=$\)\@="
diff --git a/runtime/syntax/python2.vim b/runtime/syntax/python2.vim
new file mode 100644
index 0000000000..3b30eabbae
--- /dev/null
+++ b/runtime/syntax/python2.vim
@@ -0,0 +1,345 @@
+" Vim syntax file
+" Language:	Python 2
+" Maintainer:	Zvezdan Petkovic <zpetkovic@acm.org>
+" Last Change:	2016 Oct 29
+" Credits:	Neil Schemenauer <nas@python.ca>
+"		Dmitry Vasiliev
+"
+"		This version is a major rewrite by Zvezdan Petkovic.
+"
+"		- introduced highlighting of doctests
+"		- updated keywords, built-ins, and exceptions
+"		- corrected regular expressions for
+"
+"		  * functions
+"		  * decorators
+"		  * strings
+"		  * escapes
+"		  * numbers
+"		  * space error
+"
+"		- corrected synchronization
+"		- more highlighting is ON by default, except
+"		- space error highlighting is OFF by default
+"
+" Optional highlighting can be controlled using these variables.
+"
+"   let python_no_builtin_highlight = 1
+"   let python_no_doctest_code_highlight = 1
+"   let python_no_doctest_highlight = 1
+"   let python_no_exception_highlight = 1
+"   let python_no_number_highlight = 1
+"   let python_space_error_highlight = 1
+"
+" All the options above can be switched on together.
+"
+"   let python_highlight_all = 1
+"
+""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
+" NOTE: This file is a copy of the last commit of runtime/syntax/python.vim
+" that still supported Python 2. There is support for Python 3, up to 3.5,
+" and it was kept in the file as is, because it supports the straddling code
+" (Python 2 and 3 compatible) better.
+""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
+
+" quit when a syntax file was already loaded.
+if exists("b:current_syntax")
+  finish
+endif
+
+" We need nocompatible mode in order to continue lines with backslashes.
+" Original setting will be restored.
+let s:cpo_save = &cpo
+set cpo&vim
+
+if exists("python_no_doctest_highlight")
+  let python_no_doctest_code_highlight = 1
+endif
+
+if exists("python_highlight_all")
+  if exists("python_no_builtin_highlight")
+    unlet python_no_builtin_highlight
+  endif
+  if exists("python_no_doctest_code_highlight")
+    unlet python_no_doctest_code_highlight
+  endif
+  if exists("python_no_doctest_highlight")
+    unlet python_no_doctest_highlight
+  endif
+  if exists("python_no_exception_highlight")
+    unlet python_no_exception_highlight
+  endif
+  if exists("python_no_number_highlight")
+    unlet python_no_number_highlight
+  endif
+  let python_space_error_highlight = 1
+endif
+
+" Keep Python keywords in alphabetical order inside groups for easy
+" comparison with the table in the 'Python Language Reference'
+" https://docs.python.org/2/reference/lexical_analysis.html#keywords,
+" https://docs.python.org/3/reference/lexical_analysis.html#keywords.
+" Groups are in the order presented in NAMING CONVENTIONS in syntax.txt.
+" Exceptions come last at the end of each group (class and def below).
+"
+" Keywords 'with' and 'as' are new in Python 2.6
+" (use 'from __future__ import with_statement' in Python 2.5).
+"
+" Some compromises had to be made to support both Python 3 and 2.
+" We include Python 3 features, but when a definition is duplicated,
+" the last definition takes precedence.
+"
+" - 'False', 'None', and 'True' are keywords in Python 3 but they are
+"   built-ins in 2 and will be highlighted as built-ins below.
+" - 'exec' is a built-in in Python 3 and will be highlighted as
+"   built-in below.
+" - 'nonlocal' is a keyword in Python 3 and will be highlighted.
+" - 'print' is a built-in in Python 3 and will be highlighted as
+"   built-in below (use 'from __future__ import print_function' in 2)
+" - async and await were added in Python 3.5 and are soft keywords.
+"
+syn keyword pythonStatement	False None True
+syn keyword pythonStatement	as assert break continue del exec global
+syn keyword pythonStatement	lambda nonlocal pass print return with yield
+syn keyword pythonStatement	class def nextgroup=pythonFunction skipwhite
+syn keyword pythonConditional	elif else if
+syn keyword pythonRepeat	for while
+syn keyword pythonOperator	and in is not or
+syn keyword pythonException	except finally raise try
+syn keyword pythonInclude	from import
+syn keyword pythonAsync		async await
+
+" Decorators (new in Python 2.4)
+" A dot must be allowed because of @MyClass.myfunc decorators.
+syn match   pythonDecorator	"@" display contained
+syn match   pythonDecoratorName	"@\s*\h\%(\w\|\.\)*" display contains=pythonDecorator
+
+" Python 3.5 introduced the use of the same symbol for matrix multiplication:
+" https://www.python.org/dev/peps/pep-0465/.  We now have to exclude the
+" symbol from highlighting when used in that context.
+" Single line multiplication.
+syn match   pythonMatrixMultiply
+      \ "\%(\w\|[])]\)\s*@"
+      \ contains=ALLBUT,pythonDecoratorName,pythonDecorator,pythonFunction,pythonDoctestValue
+      \ transparent
+" Multiplication continued on the next line after backslash.
+syn match   pythonMatrixMultiply
+      \ "[^\\]\\\s*\n\%(\s*\.\.\.\s\)\=\s\+@"
+      \ contains=ALLBUT,pythonDecoratorName,pythonDecorator,pythonFunction,pythonDoctestValue
+      \ transparent
+" Multiplication in a parenthesized expression over multiple lines with @ at
+" the start of each continued line; very similar to decorators and complex.
+syn match   pythonMatrixMultiply
+      \ "^\s*\%(\%(>>>\|\.\.\.\)\s\+\)\=\zs\%(\h\|\%(\h\|[[(]\).\{-}\%(\w\|[])]\)\)\s*\n\%(\s*\.\.\.\s\)\=\s\+@\%(.\{-}\n\%(\s*\.\.\.\s\)\=\s\+@\)*"
+      \ contains=ALLBUT,pythonDecoratorName,pythonDecorator,pythonFunction,pythonDoctestValue
+      \ transparent
+
+syn match   pythonFunction	"\h\w*" display contained
+
+syn match   pythonComment	"#.*$" contains=pythonTodo,@Spell
+syn keyword pythonTodo		FIXME NOTE NOTES TODO XXX contained
+
+" Triple-quoted strings can contain doctests.
+syn region  pythonString matchgroup=pythonQuotes
+      \ start=+[uU]\=\z(['"]\)+ end="\z1" skip="\\\\\|\\\z1"
+      \ contains=pythonEscape,@Spell
+syn region  pythonString matchgroup=pythonTripleQuotes
+      \ start=+[uU]\=\z('''\|"""\)+ end="\z1" keepend
+      \ contains=pythonEscape,pythonSpaceError,pythonDoctest,@Spell
+syn region  pythonRawString matchgroup=pythonQuotes
+      \ start=+[uU]\=[rR]\z(['"]\)+ end="\z1" skip="\\\\\|\\\z1"
+      \ contains=@Spell
+syn region  pythonRawString matchgroup=pythonTripleQuotes
+      \ start=+[uU]\=[rR]\z('''\|"""\)+ end="\z1" keepend
+      \ contains=pythonSpaceError,pythonDoctest,@Spell
+
+syn match   pythonEscape	+\\[abfnrtv'"\\]+ contained
+syn match   pythonEscape	"\\\o\{1,3}" contained
+syn match   pythonEscape	"\\x\x\{2}" contained
+syn match   pythonEscape	"\%(\\u\x\{4}\|\\U\x\{8}\)" contained
+" Python allows case-insensitive Unicode IDs: http://www.unicode.org/charts/
+syn match   pythonEscape	"\\N{\a\+\%(\s\a\+\)*}" contained
+syn match   pythonEscape	"\\$"
+
+" It is very important to understand all details before changing the
+" regular expressions below or their order.
+" The word boundaries are *not* the floating-point number boundaries
+" because of a possible leading or trailing decimal point.
+" The expressions below ensure that all valid number literals are
+" highlighted, and invalid number literals are not.  For example,
+"
+" - a decimal point in '4.' at the end of a line is highlighted,
+" - a second dot in 1.0.0 is not highlighted,
+" - 08 is not highlighted,
+" - 08e0 or 08j are highlighted,
+"
+" and so on, as specified in the 'Python Language Reference'.
+" https://docs.python.org/2/reference/lexical_analysis.html#numeric-literals
+" https://docs.python.org/3/reference/lexical_analysis.html#numeric-literals
+if !exists("python_no_number_highlight")
+  " numbers (including longs and complex)
+  syn match   pythonNumber	"\<0[oO]\=\o\+[Ll]\=\>"
+  syn match   pythonNumber	"\<0[xX]\x\+[Ll]\=\>"
+  syn match   pythonNu