diff --git a/tex/polyglossia.sty b/tex/polyglossia.sty
index 197a83cb..f8164c2c 100644
--- a/tex/polyglossia.sty
+++ b/tex/polyglossia.sty
@@ -992,7 +992,6 @@
   \xpg_info_msg:n{Option:~ localmarks}
   \cs_gset_nopar:Nn \__xpg_local_marks:n
   {
-	 \tl_set:Nn \xpg_tmp_lang_tl { ##1 }
 	 \DeclareDocumentCommand \markboth { m m }
 	 {
 	     \group_begin:
@@ -1001,8 +1000,8 @@
                 \cs_set_eq:cc { glossary } { relax }
                 \unrestored@protected@xdef\@themark
 		  {
-		     {\text_lowercase:n{\foreignlanguage{\xpg_tmp_lang_tl}}{\protect\@@ensure@maindir{####1}}}
-		     {\text_lowercase:n{\foreignlanguage{\xpg_tmp_lang_tl}}{\protect\@@ensure@maindir{####2}}}
+		     {\foreignlanguage{##1}{\protect\@@ensure@maindir{####1}}}
+		     {\foreignlanguage{##1}{\protect\@@ensure@maindir{####2}}}
 		  }
                 \@temptokena \expandafter{\@themark}
                 \mark_insert:nn{2e-left}{####1}
@@ -1019,7 +1018,7 @@
                \cs_set_eq:cc { index } { relax }
                \cs_set_eq:cc { glossary } { relax }
                \expandafter\@markright\@themark
-		   {\text_lowercase:n{\foreignlanguage{\xpg_tmp_lang_tl}}{\protect\@@ensure@maindir{####1}}}
+		   {\foreignlanguage{##1}{\protect\@@ensure@maindir{####1}}}
                \@temptokena \expandafter{\@themark}
                \mark_insert:nn{2e-right}{####1}
                \tl_if_empty:nF{####1}{ \mark_insert:nn{2e-right-nonempty}{####1} }