The feature must be enabled through:
Look and Feel -> Theme -> tick edit templates then apply.
(once this is done you will see "Edit templates" in your Admin menu)

The user must have the tiki_p_edit_templates permission.

Edit Template is a feature to let you edit the Smarty template files (.tpl) of your theme via the web interface.

It is also possible to let users view templates without editing

Registered users can try here:
https://themes.tiki.org/tiki-edit_templates.php

Error - When attempting to enable the Edit Templates feature you encounter a 404 page with the error You don't have permission to access tiki-edit_templates.php on this server
Possible Explanation - Some shared hosting companies have built-in security that prevents certain files from being executed. If you received an error similar to this when installing TikiWiki the same solution likely applies.
Solution - Contact your host and have them 'whitelist' or allow the file tiki-edit_css.php to be executed.

• Edit Template