Wrong grouping separators are displayed when the Mac OS has been set to the German-Germany language and locale

When converting a numerical value to text with grouping enabled, the grouping character that is used is not properly localized on a Mac. By default, the grouping character that is used when in the en-US locale is the comma character (,). When the OS locale and language has been changed to de-DE (German-Germany), the separator should be a dot instead of a comma, but a comma is still displayed.

This only occurs on a Mac. The grouping separator changes as expected on Windows.

REGRESSION:
No. This same behavior occurred in 4.20.

1. Create a new Blank Blueprint project.
2. Create a new Widget Blueprint.
3. Add a TextBlock to the Widget Blueprint.
4. In the Widget Blueprint's graph, use the ToText (Integer) node to set the text property in the TextBlock to a value that would include a grouping character (eg: 10000).
   • Ensure that Grouping is enabled (it is enabled by default).
5. In the Level Blueprint, create an instance of the Widget Blueprint on Begin Play and add it to the viewport.
6. Save the current level as the default level.
7. Package the project.
8. Change the Mac's Region to Germany and make sure Deutsch is the primary preferred language.
9. Restart the Mac.
10. Run the packaged project.

RESULT:
The text displayed in the TextBlock still uses a comma character (,) as the grouping separator.

EXPECTED:
The text displayed in the TextBlock uses a dot character (.) as the grouping separator.