cookie was modified before the i18n:beforeLocaleSwitch hook was triggered

[Ercilan]

Environment

---

• Operating System: Windows_NT
• Node Version: v22.17.0
• Nuxt Version: 4.1.2
• CLI Version: 3.28.0
• Nitro Version: 2.12.6
• Package Manager: pnpm@9.15.9
• Builder: -
• User Config: compatibilityDate, devtools, typescript, runtimeConfig, imports, hooks, nitro, routeRules, modules, app, i18n, linkChecker, seo, site, robots, sitemap, ogImage, pwa, css, build, experimental, devServer, vite
• Runtime Modules: @nuxt/eslint@1.9.0, @nuxtjs/i18n@10.1.0, @vueuse/nuxt@13.9.0, @nuxtjs/seo@3.1.0, @pinia/nuxt@0.11.2, ./modules/pwa-i18n, @vite-pwa/nuxt@1.0.4
• Build Modules: -

---

Reproduction

Not sure about the reason. On StackBlitz, npm i throws the error ERROR Cannot find native binding. npm has a bug related to optional dependencies (https://github.com/npm/cli/issues/4828). On CodeSandbox, it gets stuck at Resuming MicroVM... Still booting, please wait.

Describe the bug

my config: ssg

strategy: "prefix_except_default",
detectBrowserLanguage: {
  useCookie: true,
  cookieKey: "app-locale",
  redirectOn: "root",
  alwaysRedirect: false,
},

I have a page that users can share via its link.
To prevent other users from being forced to switch languages when visiting this URL,
I tried adding a query parameter and then checking for its presence in the i18n:beforeLocaleSwitch hook when the page is accessed.
The idea was to prioritize using the user’s existing cookie language to avoid forcing a language change.

However, in my tests I found that when directly opening that URL, by the time this hook is triggered, the browser’s cookie has already been updated to the language from the URL, so I don’t have a chance to retrieve the user’s previously set language.

---

• In addition, if redirectOn could be configured as a function, wouldn’t it be much easier to implement my requirement?

• The comment for the alwaysRedirect option in the code says: Always redirect to the detected locale, not just on first visit, which doesn’t match the documentation for alwaysRedirect. This initially confused me about its relationship with redirectOn: "all".
  My current understanding is(is this right?):

  • alwaysRedirect: whether to always force a redirect to the language stored in the cookie.

  • redirectOn: under what circumstances to redirect to the language detected by detectBrowserLanguage (including the language in the route? and with the route language having higher priority?).

Additional context

No response

Logs

[Ercilan]

A demo repo: https://github.com/Ercilan/NuxtI18nDebug