I've already reported this as bug via report wizard, but wanna tell here about the problem.
Since Opera updates to v33, it has the sae bug, that was in Chrome v46: https://code.google.com/p/chromium/issues/detail?id=543018
This refers to bug https://codereview.chromium.org/1401923005/ and is solved in Chrome 46.0.2490.80
We've got many user's who works on Opera and looks like they are updating to v33.
The onliest way to solve the problem now is to disable Chrome PDF Viewer in :plugins and to use another PDF Viewing software.