$oldocchandle$->op() changes $curocc, but curoccvideo doesn't follow

Author: ulrichmerkel@web.de (ulrich-merkel)

scenario: we have a multi-occ form and turned curoccvideo on. - positioned in occurence 1, we saved the occhandle to $oldocchandle$ - we use the mouse to go to occurence 3, which is now highlited. - from a DTLF, we start: $oldocchandle$->op - the highlited occurence is still 3, but $curocc returns 1.   So tests results in: using an occhandle->op() changes the active path