The grid is mounted inside Big Picture as a component, so it shares Big Picture's host, and its
direction is written onto Big Picture itself. Its profile-config carried only the list, so its
language fell through to ?lang= on the page. An English page opened with ?lang=ar therefore laid
the whole of Big Picture out right-to-left, English included.
The grid now receives the host's language under both keys, locale and lang.
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