Screen Magnification (Zoom) gesture broken! -- "scroll gesture to zoom" not working (Mojave)

The beloved "scroll gesture with modifier keys to zoom" (that you set up in Accessibility preferences) in Mojave has just stopped working. I REALLY liked this screen magnifying option, where I could press CTRL and do a two fingers up gesture on the trackpad to magnify the screen. It just completely stopped working recently. Because of a MacOS update to Mojave? Because I installed SnagIt? Any ideas to get it working again? I REALLY need it!!! I tried messing with all the Zoom options in the Accessibility pane of System Preferences...still doesn't work....Thank you.

MacOS 10.14.5, iMac 2017