4 files changed, 11 insertions, 5 deletions
diff --git a/macros/luatex/latex/showhyphenation/showhyphenation.lua b/macros/luatex/latex/showhyphenation/showhyphenation.lua
index ff763be250..72f964932c 100644
--- a/macros/luatex/latex/showhyphenation/showhyphenation.lua
+++ b/macros/luatex/latex/showhyphenation/showhyphenation.lua
@@ -10,7 +10,7 @@
 -- and version 1.3c or later is part of all distributions of
 -- LaTeX version 2009/09/24 or later.
 
--- Version: 0.1
+-- Version: 0.1a
 
 local FLOOR = math.floor
 
@@ -128,7 +128,11 @@ local function find_glyph ( n, d, kern_value )
             if line_end and n.user_id == 848485 then
                 ligtype_mark = true
             end
-            n = d ( n )
+            if d ( n ) then
+                n = d ( n )
+            else
+                return false
+            end
         end
         if n.replace then
             local REPLACE = n.replace
@@ -214,7 +218,9 @@ local function hyphenation_points ( head )
             end
             local prev_next_glyph = n
             local ligtype_mark = nil
-            prev_next_glyph, prev_next_kern, ligtype_mark = find_glyph ( prev_next_glyph, DIR, 0 )
+            if find_glyph ( prev_next_glyph, DIR, 0 ) then
+                prev_next_glyph, prev_next_kern, ligtype_mark = find_glyph ( prev_next_glyph, DIR, 0 )
+            end
             head = AB ( head, prev_next_glyph, NEW ( WI, pdfliteral ) )
             lig_add = lig_add + ( prev_next_kern + prev_next_kern_lig ) * f
             DIR ( prev_next_glyph ).mode = 0
diff --git a/macros/luatex/latex/showhyphenation/showhyphenation.pdf b/macros/luatex/latex/showhyphenation/showhyphenation.pdf
index bbcefb44b5..a0ce34f5e5 100644
--- a/macros/luatex/latex/showhyphenation/showhyphenation.pdf
+++ b/macros/luatex/latex/showhyphenation/showhyphenation.pdf
diff --git a/macros/luatex/latex/showhyphenation/showhyphenation.sty b/macros/luatex/latex/showhyphenation/showhyphenation.sty
index 866d39c9db..ee088450a0 100644
--- a/macros/luatex/latex/showhyphenation/showhyphenation.sty
+++ b/macros/luatex/latex/showhyphenation/showhyphenation.sty
@@ -10,7 +10,7 @@
 % and version 1.3c or later is part of all distributions of
 % LaTeX version 2009/09/24 or later.
 
-\ProvidesPackage{showhyphenation}[2022/04/17 v0.1 Show hyphenation points]
+\ProvidesPackage{showhyphenation}[2022/06/13 v0.1a Marking of hyphenation points]
 \RequirePackage{ifluatex,luatexbase}
 
 \ifluatex
diff --git a/macros/luatex/latex/showhyphenation/showhyphenation.tex b/macros/luatex/latex/showhyphenation/showhyphenation.tex
index d0c376bf80..84dba3622d 100644
--- a/macros/luatex/latex/showhyphenation/showhyphenation.tex
+++ b/macros/luatex/latex/showhyphenation/showhyphenation.tex
@@ -352,7 +352,7 @@ end
 
 \title{The showhyphenation package\vspace{.25\baselineskip}\\\superlarge{}\directlua{luatexbase.remove_from_callback ( "post_linebreak_filter", "show hyphenation points in postline" ) luatexbase.remove_from_callback ( "hpack_filter", "show hyphenation points in hpack" )}Marking of hyphenation points}%
 \author{\sublarge{}Thomas Kelkel\vspace{-.25\baselineskip}\\\sublarge{}kelkel@emaileon.de\vspace{-.25\baselineskip}}%
-\date{\addfontfeature{LetterSpace=2}\sublarge{}2022/05/31\quad{}v0.1}%
+\date{\addfontfeature{LetterSpace=2}\sublarge{}2022/06/13\quad{}v0.1a}%
 \maketitle
 
 \hyphenation{pack-age}