Is i18n v9 compatible with nuxt 3.15?

[rowild]

I am trying to get i18n v0 running on my Nuxt 3.15 app since almost a week now, so far unsuccessfully. Even all the AIs like Bolt, Claude and ChatGPT fail to find the error. Some keys to properly setup the i18n.config and the folder structure can be found in the migration guide, those lead at least to a working start-up process. But in my project the language switch, when clicked, complains about "Header.vue:730 [intlify] Not found 'language.select' key in 'de' locale messages." – which is wrong, because it is there.

I recreate a minimal Stackblitz project (without the language.select problem mentioned above): https://stackblitz.com/edit/sb1-uukrlcbj?file=nuxt.config.ts

I also tried to use Nuxt 4's new folder structure, but that hasn't been successful either.

I would be very helpful if someone could clarify, if using i18n with Nuxt 3 is even the way to go or not. And if it is, maybe someone could pinpoint the error?

Thank you!