FYI: "wm-license-information-description" is contained in WikimediaLicenseTexts.i18n.php [1] within the WikimediaLicenseTexts Extension [2]
Also, in regards to your other question:
does that dump not contain all content minus history?
Yes, this dump is essentially complete [3]
It took me a while to figure this out on my own, but MediaWiki messages generally come from these locations:
* MessagesXX.php where XX is the language (EX: MessagesEn.php) * The [[MediaWiki]] namespace in a given wiki * Extensions and any of the .18n.php files contained within [4]
Hope this helps.
[1]: https://git.wikimedia.org/blob/mediawiki%2Fextensions%2FWikimediaMessages/65... [2]: https://www.mediawiki.org/wiki/Extension:WikimediaLicenseTexts [3]: Note that they do not have the User and Talk namespaces [4]: For the last, I find the following extensions are generally enough to include most of the basic messages * CategoryTree.i18n.magic * CategoryTree.i18n * Cite.i18n * Disambiguator.i18n.magic * ImageMap.i18n * ParserFunctions.i18n.magic * ParserFunctions.i18n * Poem.i18n * Scribunto.i18n * Scribunto.magic * SpecialCite.i18n * Wikibase.i18n * WikibaseClient.i18n.magic * WikiEditor.i18n * WikimediaLicenseTexts.i18n * WikimediaMessages.i18n