diff --git a/runtime/ftplugin/8th.vim b/runtime/ftplugin/8th.vim
index 1430118..ad04f9a 100644
--- a/runtime/ftplugin/8th.vim
+++ b/runtime/ftplugin/8th.vim
@@ -1,9 +1,10 @@
 " Vim ftplugin file
 " Language:	8th
 " Version:	any
-" Last Change:	2015/11/08
+" Last Change:	2021 Sep 20
+" Last Change:	2021/09/20
 " Maintainer:	Ron Aaron <ron@aaron-tech.com>
-" URL:          https://8th-dev.com/
+" URL:		https://8th-dev.com/
 " Filetypes:	*.8th
 " NOTE: 	8th allows any non-whitespace in a name, so you need to do:
 " 		setlocal iskeyword=!,@,33-35,%,$,38-64,A-Z,91-96,a-z,123-126,128-255
@@ -14,12 +15,13 @@
  finish
 endif
 
-" Don't load another plugin for this buffer
+" Don't load another 8th plugin for this buffer
 let b:did_8thplugin = 1
 
 setlocal ts=2 sts=2 sw=2 et
-setlocal com=s1:/*,mb:*,ex:*/,:\|,:\\
+setlocal com=s1:/*,mb:*,ex:*/,b:--,be:\\
 setlocal fo=tcrqol
 setlocal matchpairs+=\::;
 setlocal iskeyword=!,@,33-35,%,$,38-64,A-Z,91-96,a-z,123-126,128-255
 setlocal suffixesadd=.8th
+let b:undo_ftplugin = "setlocal ts< sts< sw< et< com< fo< mps< isk< sua<"
diff --git a/runtime/ftplugin/c.vim b/runtime/ftplugin/c.vim
index 70e54b3..b6aed9c 100644
--- a/runtime/ftplugin/c.vim
+++ b/runtime/ftplugin/c.vim
@@ -1,7 +1,7 @@
 " Vim filetype plugin file
 " Language:	C
 " Maintainer:	Bram Moolenaar <Bram@vim.org>
-" Last Change:	2020 Feb 01
+" Last Change:	2021 Sep 21
 
 " Only do this when not done yet for this buffer
 if exists("b:did_ftplugin")
@@ -40,8 +40,11 @@
 
 " When the matchit plugin is loaded, this makes the % command skip parens and
 " braces in comments properly.
-let b:match_words = '^\s*#\s*if\(\|def\|ndef\)\>:^\s*#\s*elif\>:^\s*#\s*else\>:^\s*#\s*endif\>'
-let b:match_skip = 's:comment\|string\|character\|special'
+if !exists("b:match_words")
+  let b:match_words = '^\s*#\s*if\(\|def\|ndef\)\>:^\s*#\s*elif\>:^\s*#\s*else\>:^\s*#\s*endif\>'
+  let b:match_skip = 's:comment\|string\|character\|special'
+  let b:undo_ftplugin ..= " | unlet! b:match_skip b:match_words"
+endif
 
 " Win32 can filter files in the browse dialog
 if (has("gui_win32") || has("gui_gtk")) && !exists("b:browsefilter")
@@ -62,6 +65,7 @@
 	  \ "C++ Source Files (*.cpp *.c++)\t*.cpp;*.c++\n" .
 	  \ "All Files (*.*)\t*.*\n"
   endif
+  let b:undo_ftplugin ..= " | unlet! b:browsefilter"
 endif
 
 let &cpo = s:cpo_save
diff --git a/runtime/ftplugin/gprof.vim b/runtime/ftplugin/gprof.vim
index d4547ae..d8974bc 100644
--- a/runtime/ftplugin/gprof.vim
+++ b/runtime/ftplugin/gprof.vim
@@ -1,6 +1,7 @@
-" Language:    gprof
-" Maintainer:  Dominique Pelle <dominique.pelle@gmail.com>
-" Last Change: 2021 Apr 08
+" Language:     gprof
+" Maintainer:   Dominique Pelle <dominique.pelle@gmail.com>
+" Contributors: Doug Kearns <dougkearns@gmail.com>
+" Last Change:  2021 Sep 19
 
 " When cursor is on one line of the gprof call graph,
 " calling this function jumps to this function in the call graph.
@@ -9,7 +10,7 @@
 endif
 let b:did_ftplugin=1
 
-fun! <SID>GprofJumpToFunctionIndex()
+func! <SID>GprofJumpToFunctionIndex()
   let l:line = getline('.')
   if l:line =~ '[\d\+\]$'
     " We're in a line in the call graph.
@@ -22,11 +23,14 @@
     call search('^\[\d\+\].*\d\s\+' .  escape(@", '[]*.') . '\>', 'sW')
     norm! zz
   endif
-endfun
+endfunc
 
-" Pressing <C-]> on a line in the gprof flat profile or in
-" the call graph, jumps to the corresponding function inside
-" the flat profile.
-map <buffer> <silent> <C-]> :call <SID>GprofJumpToFunctionIndex()<CR>
+if !exists("no_plugin_maps") && !exists("no_gprof_maps")
+  " Pressing <C-]> on a line in the gprof flat profile or in
+  " the call graph, jumps to the corresponding function inside
+  " the flat profile.
+  map <buffer> <silent> <C-]> :call <SID>GprofJumpToFunctionIndex()<CR>
+  let b:undo_ftplugin = "silent! unmap <buffer> <C-]>"
+endif
 
 " vim:sw=2 fdm=indent