Giants Editor Preferences Scripting Tab Farming Simulator 25 (FS25).
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In Giants Editor when you use file -> preferences as shown below.
Then click scripting tab and you see this.
Additional Include Directories
Editor Script Directories are directories which are searched for LUA scripts to be used in Giants Editor.
While you can configure multiple directories here, in order to keep things sane its highly recommended that you consolidate all your scripts which are proven to be working for specific Giants Editor version in a single directory.