nemmo\attachments\behaviors\FileBehavior::getInitialPreviewConfig PHP Method

    public function getInitialPreviewConfig()
    {
        $initialPreviewConfig = [];
        $userTempDir = $this->getModule()->getUserDirPath();
        foreach (FileHelper::findFiles($userTempDir) as $file) {
            $filename = basename($file);
            $initialPreviewConfig[] = ['caption' => $filename, 'url' => Url::to(['/attachments/file/delete-temp', 'filename' => $filename])];
        }
        foreach ($this->getFiles() as $index => $file) {
            $initialPreviewConfig[] = ['caption' => "{$file->name}.{$file->type}", 'url' => Url::toRoute(['/attachments/file/delete', 'id' => $file->id])];
        }
        return $initialPreviewConfig;
    }