How to keep Preview from destroying files?
I have a lot of trouble with Preview destroying my files. I want to know how to keep Preview from destroying my fiiles.
I am clumsy, so I slip, and I use scrolling software. When I slip, Preview decides I have edited my file-- I have not-- and Preview reprocesses the file and replaces the orginal with a new version. If I need the original, it is gone. If I need a text layer, and it isn't in the Roman alphabet, it is gone. If I need to avoid reformatting in Quartz due to incompatibilities with other pdf tools, it is reformatted anyway.
I think Preview used to have a setting to keep it from destroying my files, but the 9.0 update reverted my other settings, and seems to have deleted this setting. I use "ask to keep changes" under System Preferences > General, but that doesn't stop Preview. It's destroy, destroy, destroy.
MacBook Air (11-inch Mid 2013), macOS Sierra (10.12.6)