I was trying to make my favorite font, Inconsolata-dz, render with the same nice tight line spacing of the default Menlo. So I set:
"font_size": 12.0,
"font_face": "Inconsolata-dz",
"line_padding_top": -2.75,
But then I discovered that when I moved the cursor off the first line of the file, it wouldn’t go back up to line 1! It stops at line 2, unless I use Command-Up to go to the beginning of the file. Removing the line_padding_top fixes it. This happens with any font, not just Inconsolata-dz.