Bug-R15b7-Fusion - Scrollwheel inconsistent behaviour

Hi,
When using the scrollwheel in the Media, Edit and Grade page, it functions as a zoom. But in the Fusion page it only scrolls the image vertically. I would expect it to behave the same as the other pages.
Please see video (and also notice the incredible lag between the pages!)

http://www.gfycat.com/GroundedBigheartedHapuka
Tested on Centos and Win10
When using the scrollwheel in the Media, Edit and Grade page, it functions as a zoom. But in the Fusion page it only scrolls the image vertically. I would expect it to behave the same as the other pages.
Please see video (and also notice the incredible lag between the pages!)

http://www.gfycat.com/GroundedBigheartedHapuka
Tested on Centos and Win10