Translations:Extension:MultiUpload/12/en

In both examples of adding links to this extension in sidebar>Special:MyLanguage/MediaWiki:Sidebar|MediaWiki:Sidebar, if only "multipleupload" or "multipleupload-toolbox" shows in the sidebar, you may have to navigate in your wiki to "MediaWiki:Multipleupload" or "MediaWiki:Multipleupload-toolbox" and create the pages with the messages that are already shown.