Can't seem to insert contact tokens into receipt subjects

I can't seem to insert contact tokens into receipt subjects. It always results in a Smarty error (pasted at bottom). I was able to re-create the error at http://d45.demo.civicrm.org/civicrm/contribute/transact?reset=1&id=1&action=preview by inserting

{contact.display_name} to http://d45.demo.civicrm.org/civicrm/admin/messageTemplates/add?action=update&id=47&reset=1


User error: Smarty error: [in string:{strip}[TEST]{contact.display_name} {if $is_pay_later}{ts}Invoice{/ts}{else}{ts}Receipt{/ts}{/if} - {$title} {/strip} line 1]: syntax error: unrecognized tag: contact.display_name (Smarty_Compiler.class.php, line 446) in Smarty->trigger_error() (line 1094 of /srv/buildkit/build/d45/sites/all/modules/civicrm/packages/Smarty/Smarty.class.php).
User error: Smarty error: [in string:{strip}[TEST]{contact.display_name}{if $is_pay_later} {ts}Invoice{/ts}{else}{ts}

Receipt

{/ts} {/if}

- {$title}

{/strip}

line 1]: syntax error: unrecognized tag '' (Smarty_Compiler.class.php, line 590) in Smarty->trigger_error() (line 1094 of /srv/buildkit/build/d45/sites/all/modules/civicrm/packages/Smarty/Smarty.class.php).