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ScriptedImporterAttribute.fileExtensions

public string[] fileExtensions;

Description

List of file name extensions (not including the leading period character) that the scripted importer handles.

using UnityEngine;
using UnityEditor.AssetImporters;

[ScriptedImporter(1, new[] {"cb", "cube"})] public class CubeImporter : ScriptedImporter { public override void OnImportAsset(AssetImportContext ctx) { // ... } }