The biggest risk of "Portable" software is malware. Because it doesn't install, antivirus software cannot sandbox it as easily. Always ensure:
Note: The official YouTubeByClick website primarily sells the installer version. "Portable" versions are often distributed by third-party "portable app" providers or can be created manually. youtubebyclick portable
The primary purpose of YouTube By Click is to facilitate media downloading. The biggest risk of "Portable" software is malware