The page at https://dumps.wikimedia.org/other/pagecounts-ez/ is out of date, and it is unclear how to suggest changes to this page, hence logging this issue here. In particular, the page says that the prefixes for each row are (I quote) "one of b (wikibooks), k (wiktionary), n (wikinews), o (wikivoyage), q (wikiquote), s (wikisource), v (wikiversity), z (wikipedia)".
However, there are rows in the most recent -totals file (pagecounts-2017-09-views-ge-5-totals.bz2) with undocumented prefixes like en.d, en.m, en.m.d, en.zero It seems as if the .m stats correspond to mobile web views, but it is not clear to me what e.g. .m.d rows correspond to.