Just speaking off the cuff, I don't think Opera or Vivaldi have any interest whatsoever in implementing that any time soon. I think they're wasteful and annoying. If you're doing things through a remote graphical environment (RDP, VNC, TeamViewer, etc.) and it just so happens your link to that remote site isn't the best, it makes that session all the more annoying. But...KISS was killed a long time ago, "everything possible" has to slide or fade or zoom or do something. You couldn't possibly just update the screen, it "has to" morph somehow. This is all despite every once in a while this feature is requested. I think it's too important to the authors of the software that the browser does these things, and they fear if they don't do it, people will not like their software and use something else instead.