Board Thread:Wikia Discussion/@comment-25683568-20150318062713/@comment-26154973-20150608113341

lang="ja" doesn't make any difference on Firefox for me, it uses legacy "MS PGothic" (Win 5) by default (which doesn't display some glyphs, e.g. 曾, right), that is why Template:SpanJa also sets "Meiryo" (default for Win 6 and later) and only then generic "sans-serif".

No problems on Chrome or IE11 it seems, https://bugzilla.mozilla.org/show_bug.cgi?id=1016792#c2