[Bug Report]kissanime.com - HTML5 Player isn't working only Flash.
HTML5 player works in opera and Edge Example http://kissanime.com/Anime/Overlord/Episode-012?id=11698 Thanks..
Vivaldi doesn't (yet) support H.264-Video-Codecs. You can look up what HTML5-Video-Codecs (or "types") are supported in a browser here:
This should be working with the latest snapshot release.