This message uses "e.g." incorrectly. It means "for example" but that makes no sense in this context. So "i.e." should be used instead:
The page "$1" contains the entire wiki URL. Make sure you only enter the page title, i.e. the part of the URL after <code>/wiki/</code>.
Change 793801 had a related patch set uploaded (by Klein Muçi; author: Klein Muçi):
[mediawiki/extensions/GWToolset@master] MediaWiki:Gwtoolset-page-title-contains-url/en: Change "e.g." to "i.e."
Change 793801 merged by jenkins-bot:
[mediawiki/extensions/GWToolset@master] MediaWiki:Gwtoolset-page-title-contains-url/en: Change "e.g." to "i.e."