The reason why video is not playing (after a update) in Opera is due to the fact that the H264 codec is not supported (ie Opera does not pay money to the license owner of the proprietary H264 codec)

Use the opensource X264 codec which is you can download from the software manager tab in Ubuntu, Mint, etcetra
It worked for me with ubuntu and Mint. Otherwise this link could be helpfull: https://forums.opera.com/topic/34659/opera-linux-browser-h-264-support-through-x264-open-source-codec