Does translation affect plugin itself?

[pea3nut]

Hello,

I add some translation file in ./index.js like that:

uiExports: {
      translations: [
        resolve(__dirname, './translations/en.json'),
        resolve(__dirname, './translations/zh.json'),
        resolve(__dirname, './translations/zh-TW.json')
      ],
}

I found that the key of UI-WELCOME_MESSAGE has affected the loading message.

But when I use orther key in index.html like this:

<h1>{{ 'msg' | translate }}</h1>

The en.json:

{
  "UI-WELCOME_MESSAGE": "LoadingKKKKKKKKK",
  "msg": "hello",
}

It shows me like this:

---

msg

---

The key of UI-WELCOME_MESSAGE is effective but msg is not, why?