diff --git a/tagpdf-struct.dtx b/tagpdf-struct.dtx
index e1e3f5bd..16b8f114 100644
--- a/tagpdf-struct.dtx
+++ b/tagpdf-struct.dtx
@@ -1946,6 +1946,10 @@
 \tl_new:N   \l_@@_attr_value_tl
 \prop_new:N \g_@@_attr_objref_prop %will contain obj num of used attributes
 %    \end{macrocode}
+% This seq is currently kept for compability with the table code.
+%    \begin{macrocode}
+\seq_new:N\g_@@_attr_class_used_seq
+%    \end{macrocode}
 % \end{variable}
 % \subsection{Commands and keys}
 % \begin{macro}{\@@_attr_new_entry:nn,role/new-attribute (setup-key), newattribute (deprecated)}
diff --git a/tagpdf-tree.dtx b/tagpdf-tree.dtx
index 0b92a5bf..68d28670 100644
--- a/tagpdf-tree.dtx
+++ b/tagpdf-tree.dtx
@@ -505,6 +505,14 @@
 \cs_new_protected:Npn \@@_tree_write_classmap:
   {
     \tl_clear:N \l_@@_tmpa_tl
+%    \end{macrocode}
+% We process the older sec for compability with the table code. 
+% TODO: check if still needed
+%    \begin{macrocode}
+    \seq_map_inline:Nn \g_@@_attr_class_used_seq
+     {
+       \prop_gput:Nnn \g_@@_attr_class_used_prop {##1}{}
+     }
     \prop_map_inline:Nn \g_@@_attr_class_used_prop
      {
        \tl_put_right:Ne \l_@@_tmpa_tl