A somewhat belated note about this topic...
The official Wikimedia blog published a post about this:
It's the first post on that blog to be available in Bashkir translation (yay to our volunteers), but there's a more interesting point.
In the comments to the post there's a question: Can the same be done for Thai? My immediate reaction was surprise: Despite having a relatively complex script, Thai has probably been the best-supported Southeast Asian language in software for a long time; doesn't it have collation support in ICU already?
It looks like Thai is supported there already, but the collation for it is not enabled on our sites. Enabling it is probably easy (see
https://phabricator.wikimedia.org/T176434 ), but this raises the question: Would this be a good idea to set a default collation in MediaWiki core rather than doing it on each *site* separately?
Currently, collation rules are not enabled by default, even if ICU supports them. Categories will show page names in the order of Unicode characters. If another collation is enabled in the site configuration, then it will be used. So this must be done manually for Wikipedia, Wiktionary, Wikivoyage, etc., and it must also be done by each non-Wikimedia MediaWiki user. To me it makes sense that if the site language is Thai, the default Thai collation will be used, unless specified otherwise, and the same thinking should be for all other languages. However, I might be missing something, and there are much better collation experts than me on this mailing list, so I'd love to hear your opinions.
Thanks!