Unresponsive and slow scrolling of the file diff panel

Up to 1.8.x the diff view scrolling was instantaneous and quick. In 1.9.3 there is a noticeable delay before the new view starts scrolling and scrolling itself is also slower than in the previous version, sometimes so slow it fails to register a rapid two-finger swipe at all, sometimes pausing for a short moment and then suddenly jumping up or down.

This makes quick scanning much slower and error-prone as the delay makes the scrolling unpredictable (in particular if it fails to register the scolling gesture at all) and requires much more swiping to get the same result (looks like about 3 times more swipes are required in 1.9 as compared to 1.8).

Combine having to swipe many times more with the delays, sudden jumps and missed gesture recongition and you've got a pretty unpleaseant experience.

This is not a computer performance issue - I just had 1.8 and 1.9 running side by side and the behaviour difference is striking between the two.