In this project [Download YouTube Video Thumbnail], as you can see in the image preview there is a white box or form with an input field, image preview area, and a download button. Download button is disabled until you paste a valid YouTube video URL or other image file URL.
When you paste YouTube video URL immediately there is appears a preview of the thumbnail of that video and you can download it. This thumbnail downloader accepts all types of YouTube video URLs means long or short URLs of the videos. And it also accepts any other image file like .jpg, .jepg, .png, .gif, and .webp.
Video Tutorial of YouTube Thumbnail Downloader
You can download the source code files of this Thumbnail Downloader from this given link. Click here to download code files.