This is only a minor suggestion and not a major bug.

I am currently using mouse wheel up/down to zoom in and out when using a long range scope, which is also the default for scrolling up and down inside your inventory. When the assigned keys conflict with each other and you start scrolling in your inventory, the view in the 'background' attempts to zoom at the same time (the zooming doesn't actually work, the screen just jumps around).

This could be solved by locking the zoom function when viewing your inventory.