"Mobile devices" in the sense of T189554, i.e. clients that by default see the mobile site (more technically: that our Varnish code, according to a user agent regex there, will redirect from e.g. en.wikipedia.org to en.m.wikipedia.org unless a cookie indicates they opted into desktop).
Limited to the wikitext editor because those edits are easier to detect/count in the webrequest table, at least for the desktop interface.