Current locale is displayed incorrectly and failed to switch back from English to the "defaultLocale“ set in ”package.json“

[330GRX]

1. Set "defaultLocale" in "package.json" to "zh-cn".
2. Launch IDE
3. Press F1
4. Select the "Configure Display Language" option

Now we can see that (current) is incorrectly displayed and the actual locale is ‘en’.

And it doesn't switch to ‘zh-cn’.

The desired status is as follows:

• Theia Version:1.61.0

[msujew]

Hey @330GRX,

since the zh-cn language is listed as one of the Available languages, that means the language pack isn't installed yet. Theia will not install the language pack on startup automatically. Please add the zh-cn language pack to the builtin extensions of your app for this feature to work as expected.

[330GRX]

Hey @330GRX,

since the zh-cn language is listed as one of the Available languages, that means the language pack isn't installed yet. Theia will not install the language pack on startup automatically. Please add the zh-cn language pack to the builtin extensions of your app for this feature to work as expected.

Hey @msujew ,Thanks for your comment.

I recorded a GIF where you can see the corresponding language pack installed in the lower left corner.Here's what happened:

1. First run:

• Locale was 'en'
• Command palette showed current language as 'zh-cn' (incorrect)
• Switched to 'en' → worked

2. Second run:

• Locale was 'en'
• Command palette still showed current as 'zh-cn'
• Tried switching to 'zh-cn' → failed

3. Third run:

• Locale was 'en'
• Switched to 'ja' in command palette → worked

4. Fourth run:

• Locale was 'ja'
• Switched to 'zh-cn' in command palette → worked

5. Fifth run:

• Locale was 'zh-cn'
• Switched to 'en' → worked

6. Sixth run:

• Locale was 'en'
• But command palette still displayed current language as 'zh-cn'

Key observations:

• The command palette consistently misreports 'zh-cn' as current when locale is 'en'
• All language switches work except 'en'→'zh-cn' ("defaultLocale" in "package.json" is set to "zh-cn".)

[msujew]

Please create an issue for this.

[330GRX]

Find the reason in #13283