Hello, I think we've got too many pages on Special:WantedPages, many of which are associated with variables used in translation units. So, each of these pages would need to have the following content:
<includeonly>{{BASEPAGENAME}}</includeonly><noinclude>{{Translation variable notice}}</noinclude>
However, this will be only for templates. On content pages, it should be:
{{Translation variable notice}}
The template "Translation variable notice" is in my sandbox: User:Keyacom/sandbox/Translation variable notice. Is it good?