Will whitelisted pages work someday?

Hey Hans,

In short, WP core does not provide a way to switch locale on a per-user basis, so we have to work around that by changing the site locale during the pageload. This is a quite common practice but has unintended side effects on certain admin screens (like changing the selected language dropdown value in Settings > General and not being able to provide translation updates on the Update Core page)

There is a separate ticket for allowing locale to switch on a per-user basis as a core feature, but they’ve run into the aformentioned problems as well:
https://core.trac.wordpress.org/ticket/29783

Until a viable solution emerges, we’ll have to keep those pages whitelisted. Sorry for the inconvenience.