Profile Settings: No Entry for Mastodon handle

In the personal profile settings page, there is a entry field for a Twitter handle.
Is it possibel to add custom handles, for example one for Mastodon?

Unsure, but here is the admin documentation for reference.

On wich git repo may one add a issue for adding a flexible socialMedia property for the user profile setting?

It would either be under Contacts or possibly the server repo afaik.

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