Thanks for replying. I think you mean these two settings:
I’ve enabled both, but it’s not helping. The login page is shown in the user’s browser’s language, but every other page is shown in default/English. They then must click their avatar, a downward pointing caret, a “preferences” tab, an “interface” tab, a “language” dropdown, search for their language, click their choice, click the “save” button, and then refresh their browser. That’s a lot of steps!