--- loncom/xml/lontex.pm	2008/11/24 17:17:52	1.13
+++ loncom/xml/lontex.pm	2023/12/22 13:38:01	1.14
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # TeX Content Handler
 #
-# $Id: lontex.pm,v 1.13 2008/11/24 17:17:52 jms Exp $
+# $Id: lontex.pm,v 1.14 2023/12/22 13:38:01 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -103,8 +103,15 @@ sub handler {
 						($env{'form.inhibitmenu'} 
 						 eq 'yes'), }));
 
+  my $displaymode;
+  if (&Apache::lonnet::EXT('resource.0.texdisplay') =~ /^(tth|mathjax)$/i) {
+      $displaymode = $1;
+  }
+  if ($env{'form.texengine'} =~ /^(tth|mathjax)$/i) {
+      $displaymode = $1;
+  }
   $r->print(&Apache::lontexconvert::converted(\$texstring,
-					      $env{'form.texengine'}));
+					      $displaymode));
   $r->print(&footer());
 
   return OK;