Changing the default locale setting currently does nothing, as it does not save. Tested on Meta and Try.
Change language
Hit save
Refresh page: Language is still English (or, I’m assuming, whatever was the default language before this regression)
Edit: hmmm, seems it’s not quite as simple as I described it because language got changed on Meta now, but in settings it says it’s still English… I can change it to any language except English, because the interface insists that this is the current language in use.
Seems fine now! Language is changed immediately upon refresh and the language selector does not get stuck on the previous default locale.
For some reason I had to do a “Empty cache and hard reload” to get the new locale to kick in in incognito mode, but that’s probably just a Chrome quirk.