For each site the support needs to be added separately. Not sure if we could borrow WordPress core’s oEmbed functionality to add some 30 sites instantly, but as there are thousands of video sites, only a portion of them can be covered.
PinkBike.com seems to have an easy enough logic for the thumbnails. With the example video address https://www.pinkbike.com/video/252627/ the example thumb address is https://av1.pinkbike.org/vt/1/vt-252627.jpg, found in the page’s HTML source code. However, I didn’t see a way to show the video as part of my WordPress site.
Mpora.com uses videos that seem very similar to Vimeo, but doesn’t have information about their API format. They do have embed codes, though. Their own thumbnail URLs don’t follow a singular pattern. For example the video at https://video.mpora.com/watch/vlCv9OsmA/ has its tiny thumbnail at https://cdn5.video.mporatrons.com//play/tnwide/vlCv9OsmA/m/2/, where the numbers after “cdn” and “/m/” are different for each video.
Rkovachev, if you could ask Mpora.com administrators for a syntax that would always give a working thumbnail URL based on the video URL, it would cover one necessary step towards adding the support in the plugin. With PinkBike.com, it’d be necessary to know a way for embedding the videos in WordPress posts for the thumbnail support to be feasible.