How to set social media urls language agnostic in TYPO3 v13/ BP v16?

How can I set the social media channel urls language agnostic, e.g. `page.theme.socialmedia.channels.youtube.url`? I am using TYPO3 v13 and BootstrapPackage v16 using site sets and site settings.

In older versions of BP these settings were set via TypoScript constants and therefore could be overwritten via TypoScript condition.

But now the site settings are always included as the last import in the TypoScript constants hierarchy.

I also tried to remove the social media channel url settings from the site settings and to set them via TypoScript constants in my sitepackage site set. But this results in empty social media channel urls (default values from the settings.definitions.yaml in BP).

Any idea?

Start by reviewing the BootstrapPackage v16 site settings and settings.definitions.yaml, then trace how the site settings and TypoScript constants are imported in the TYPO3 v13 configuration hierarchy. Confirm the supported way to keep social media URLs language agnostic and document the resulting configuration and behavior.

Written by the indexing model from the issue text.