We recently made an update to allow for .mp4 videos as custom thumbnails for videos or any media item, instead of using gif files that can be large/download slow and be of lesser quality.
Some guidelines on how you should encode/size the .MP4 file:
- Export your .MP4 file for the Custom Thumbnail for a duration no longer than 4 seconds
- please encode your .MP4 file for Custom Thumbnail with streaming disabled in the encode
- export the .MP4 for Custom Thumbnail, at either 720x405px or 1280x720px dimension
- please remove any audio for the .MP4 file when encoding for the Custom Thumbnail
IMPORTANT: Please remember that these .MP4 files are going to be used as thumbnails in a thumbnail-first gallery so the larger the .MP4 file size and the more .MP4 custom thumbnails in a gallery, there will be more degradation in page speed for your visitors and navigating in your own Media Library can become slower.
Steps to do this are listed below:
1. Find the media item you want to upload a video thumbnail for. You can either double click on it or select it and hit edit:
2. you should then see the panel below with the custom thumbnail upload section:
We've provided a video below on the entire process: