Could we have
'sortPrepend' => [ 'ga', 'gv', 'sco', 'cy' ]
set for the Scottish Gaelic Wikipedia, gdwiki, please.
This has been discussed by the community in July and August, following the introduction of Compact Language Links to gdwiki:
with a clear consensus that we need to prioritise certain languages, including as a minimum Irish Gaelic (ga), to make the Compact Language Links more useful.
Although we did not finalise a list of languages at the time, the Admins and those involved resumed the discussion recently, and settled on this request for three linguistically related languages (ga, gv, cy) and one geographically related language (sco), and that we should invite user feedback and review the list if required in four months. (We thought, by the way, that it would have been good if the Compact Language List had been longer than nine languages, in which case we would probably have included the other two Celtic languages, br and kw.)