Did you investigate? Did you find out something?
I still cannot open any video from VK.
Also I cannot open this links from another site:
https://cdn-e2.streamable.com/video/mp4/qt2v.mp4
https://cdn-e2.streamable.com/video/mp4/mwwj.mp4
Very often I receive this sentence: This browser (Opera) does not support video playback.