Hi, from one of the last pro theme updates the portfolio feature not work as it suppose to do, also dev console throws a lot of errors when I try to navigate using categories filter.
In another site which I did some testing before, I disabled isotope filtering methods in _script-isotope-portfolio.php theme file and this errors did not show again, so I think the problem may be in the js files or jquery isotope lib.
Since I experimented this issue in a few sites I decided to drop a new site for testing purposes without plugins, just pro theme and demo content and error happens too.