Thread:Support/Enable export for all supported languages with an open Wikipedia

According to MF-Warburg the list of Wikipedias without a MessagesXx.php is: bxr, chy, cr, ki, nrm, rn, roa-rup, rw, tum, tw. Otherwise those translators will keep translate locally only, and in general those wikis will not be served well; background/example in Thread:Support/bxr.wikipedia.