Disabling the "hardware accleration" in opera setting solved at least the Youtube lags for me now. But the whole browser is still laggy like hell. Perhaps i should get back to firefox... the glourious days of opera are gone

"i figuered its an Add-On problem" - - - Would be great when you share the name of the addon, so others can test it to. I don't want to delete all my addons just for testing...

Just reinstalled Opera, is still not working

1. Uninstalled it, deleted in "AppData/Local", "AppData/Roaming" & "ProgramFiles(x86)" all Opera-related folders.
2. CCleaner to get rid of some Reg-issues
3. Fresh & clean installation of Opera
4. Opened YouTube with clean Opera and had same issue

same issue there. but Since i used the new browser a little bit more, I found it be relative laggy at all. Will try to back up my personal stuff, delte all AppData-Stuff and other opera-related folders and reinstall the whole thing tomorrow. Perhaps this will help.

Since my Opera-Client updated to the new version, my youtube bugs every time i play videos in fullscreen-mode. Than the video lags far behind the sound-files. As son as i close the full-screen-mode, the video runs at super-speed, until it reached "synced" state with the sound again, and than runs totally fine. I've already tryed other browsers like Firefox & IE. They yust work fine. Even an upgrade of Flash-player could not fix that problem for me.
Since i use Youtube really often, I can say for shure, that this problem starts right with the new Update.

Version: 29.0.1795.47 - Opera ist auf dem neuesten Stand
Update-Stream: Stable
Betriebssystem: Windows 8.1 64-bit (WoW64)