There is indeed an inconsistency between the installer and language-selector in this respect. The issue is reported in bug #1294858. That bug report is a bit 'noisy', but in comment #3 you find my idea for a solution and the reasons for it.
So even if this bug may be considered a duplicate, let's keep it for now as a reminder. After all the issue is closely related to the behavior of language-selector.
There is indeed an inconsistency between the installer and language-selector in this respect. The issue is reported in bug #1294858. That bug report is a bit 'noisy', but in comment #3 you find my idea for a solution and the reasons for it.
So even if this bug may be considered a duplicate, let's keep it for now as a reminder. After all the issue is closely related to the behavior of language-selector.