The template above may be partially or fully invisible or glitched due to the respected strings aren't entered. This is normal.

Documentation for Template doc

Usage

Place {{Template doc}} inside tags on a template page to display template documentation.
Generally template documentation should only be used on complex templates with multiple parameters. The majority of templates won't need a separate documentation subpage.
If you want to have documentation displayed without a subpage, but with the green box, use {{Doc begin}}.