Zoom inactive when hovering above the low part of clip
Zooming in-out horizontally in the multitrack doesn't work if the mouse pointer is over the lower area of a clip. (In the attached screenshot I highlighted the area.)
Additionally, when you zoom out vertically, this area doesn't decrease with the track height, so when there are many tracks, zooming in/out horizontally with Ctrl is likely to not work or be jumpy. The inactive zone only disappears when you zoom out so much that the clip gain/FX/group/stretch icons on the bottom left are not displayed anymore.