In the former version of the IBC, a thumbnail image from an uploaded video was automatically taken at 1/3 of the video’s duration. So, for a 30-second video, the system took a static image at the 10-second mark, “hoping” that the bird was visible there. Now, videos get an automatic thumbnail taken in the same way, but the system generates 5 images instead of just one, so you can choose the best one when uploading the video, or you can edit already uploaded videos to choose a better thumbnail.
For videos uploaded in the old system, you will be see a button next to “Edit” called "Regenerate thumbnails". Clicking it will trigger the extraction of 5 images and you will be able to pick the best one. New videos don't have this "Regenerate thumbnails" option because they are already generated, you just need to go to "Edit" to pick a different one. We encourage all contributors to review their favourite videos to make sure the current thumbnail is satisfactory and, if not, to change it.
This is just another small way in which we hope to improve the IBC experience for everyone!