@n1nj4lo FYI, the shift to chromium essentially occurred (version-wise) after Opera 12.17 - that is, at higher version numbers. Tab stacking in Olde Opera was incorporated at version 11 and above. Depending on one's point of view, some users feel 11.6x was the best Olde Opera version, others prefer 12.14, still other users have other preferences. Obviously, YMMV. Olde Opera versions can be downloaded directly from Opera's ftp server at ftp://ftp.opera.com/pub/opera/win/