API
The API is the part that handles mod loading and giving mods an interface to make modding easier.
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The extension loader hot loads GDevelop extensions, as they are not included in every game (unused ones are filtered out when exporting), to be able to access GDevelops full functionality inside mods.
The list of includes is generated automatically using some modifications to GDCore (to be able to access includes from javascript) and a simple script. You can find it all here: https://github.com/arthuro555/GDevelop/tree/gdmod-generate-includes-list.