Surprisingly nobody seems to have mention this yet.
I just upgraded to version 21.02.27 and noticed that the timeline zoom sliders don’t respond to the mouse wheel anymore. Same thing on the keyframe side.
OK, well, you still have plenty of other ways to change zoom including wheel while holding Ctrl over the time strip and tracks area.
This is an easy fix to make in your installed version by editing share\shotcut\qml\views\timeline\ZoomSlider.qml:
While we’re on the subject of sliders…
I also just noticed that when using the mouse wheel on filter Mask: Simple Shape parameters sliders, they only move by increments of 0.01% now. Some the same as when wheeling in the value displays on the right.
I’ve never used it that way. If I use the the mouse wheel it’s always on the timeline while pressing Ctrl. I use the sliders either by pressing the magnifying glass icons or by just clicking where in the slider I want it to zoom to.
Because you didn’t know you could do it only with the wheel or because you prefer using two hands to zoom the timeline ?
I use the magnifying glass icons and direct click in the slider too. Never used Ctrl + wheel in the timeline.
I usually have my left hand on the other side of the keyboard anyway to hit S for split, Alt to jump around the timeline faster, etc… so since it’s there and if I am in the timeline then it it’s actually faster for me to just hold Ctrl then use the mouse wheel.