src/vs/workbench/contrib/customEditor/browser/customEditors.ts/CustomEditorService/createDiffEditorInput
class CustomEditorService:	private createDiffEditorInput(
		editor: IResourceDiffEditorInput,
		editorID: string,
		group: IEditorGroup
	): DiffEditorInput {
		const modifiedOverride = CustomEditorInput.create(this.instantiationService, assertIsDefined(editor.modified.resource), editorID, group.id, { customClasses: 'modified' });
		const originalOverride = CustomEditorInput.create(this.instantiationService, assertIsDefined(editor.original.resource), editorID, group.id, { customClasses: 'original' });
		return this.instantiationService.createInstance(DiffEditorInput, editor.label, editor.description, originalOverride, modifiedOverride, true);
	}