With X Rebirth, player-created content used to change the way the game works is called "extensions". In earlier Egosoft games, player-created content is called scripts or mods.
Please note that the use of extensions or save game edits can break games either of themselves, after future game updates, or via conflict with other extensions. Consequently, Egosoft are not generally able to support modded/save-game editted games (see here for further details).
Overview
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