Thanks huwanhsin. I had 64 bit Linux so hopefully it will fix that too!

When I try to play a video from Google Photos in Opera it gives "Invalid Parameters", and it is trying to use flash player. Works ok in Chrome and Firefox (prob using HTML5). Flash player seems to work on other sites in Opera though (e.g Dailymotion)

OS is Linux Mint Rosa 17.3
Opera:44.0.2510.857
Flash player: 24,0,0,221

Does Opera not use HTML5 by default?