Hi! I'm using the Opera 33.0.
My user agent is:
Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2490.80 Safari/537.36 OPR/33.0.1990.58

But JBrowser say it's the Chrome.
If i add this code (like chrome detection) into joomla.environment.browse

elseif (preg_match('|OPR[/ ]([0-9.]+)|', $this->agent, $version))
{
    $this->setBrowser('opera');
    list ($this->majorVersion, $this->minorVersion) = explode('.', $version[1]);
}

all working nice