Someone who knows how to change the flag icon in the language pack. Thanks!

You will need to replace the images with your own. Search the root of the site for this path  /uploads/set_resources_1 images flags16.png; flags32.png

The flag icon is defined by the locale you have selected in your language pack.

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Locales

The locale you choose for a language primarily determines the number and date formatting that the suite applies.

Although each language you have installed in your community has an associated locale, the locale is chosen separately. This is because a language can often be used in more than one locale; for example, English is used in the United States and United Kingdom, although these are different locales with different date formatting.

If necessary or desirable, you can install the same language pack several times and choose a different locale for each, to give users the number/date formatting that they are used to.

5 hours ago, LoPoSt said:

You will need to replace the images with your own. Search the root of the site for this path  /uploads/set_resources_1 images flags16.png; flags32.png

Editing files in the /uploads/.../ folder is not recommended. That will be overwritten at some point. If you want to edit a theme resource, go to Themes in the ACP, then click the "Manage Resources" option on your theme.