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I made an alternative .conf for people to try out.
Fullscreen res is set to 1280x720 so if you use a 16:9 screen you should be okay, if you use a different aspect ratio set something similar (e.g. 1280x800 for 16:10 screens) but I advise against using HD or 4K resolutions.
Screentearing still exists though it is minimal.
Just a heads up, this does not fix the issues on Mac OS (like sound stuttering and screen tear), but it does on Windows. :)

This one suggested in a thread here does indeed fix it for Mac OS:
Post edited December 27, 2018 by stimpy_
To fix the aspect ratio,

1) edit the file dosbox_epin.conf
2) change the line with "fullresolution=desktop" to "fullresolution=1920x1080" (enter the resolution of your screen)

(OR fullresolution=1920x1200 for example if you have a 1920x1200 monitor)