Hi there! So, I’m not sure if this is a Mac OS (10.13.6) or BetterTouchTool issue, but the pinch-to-zoom functionality in the Finder has recently become unreliable for PDFs. Normally, I should be able to zoom in and out on the preview images of PDFs and image files in the Finder (with or without BTT), and this usually still works for image files, and sometimes works with PDFs, but it has become very inconsistent.
This applies to Magic Trackpad.
BTT 3.163
Thank you!