This template is only to be substituted, and displays a warning if not substituted correctly.

Usage:

The template is used to identify the author of an edit on a talk page if the author failed to sign the edit. There is one parameter, which is the username or IP address of the editor. This can be found in the page history. The template must be substituted or it will display a warning. This is so that the identification of the editor is permanently placed on the page and is not affected by changes to this template.

Correct substitution:

{{subst:unsigned|Foo|11:59 19 December 2024 (UTC)}}

...displays as:

—The preceding comment was added by Foo (talkcontribs) 11:59 19 December 2024 (UTC)

...while incorrect transclusion:

{{unsigned|Foo}}

...displays as:

This template must be substituted.