I opend today a glyphs file (which I created in Glyphs 2) in Glyphs 3 (3100), and I detected some wired changes. For instance, the sidebearings of small caps changed. However, when I export the font in Glyphs 3, the sidebearings are ok.
Or, components with non-automatic alignment changed to automatic, which leads to wrong widths of tabular numbers.
This is how it looks in glyphs 2 and how it is intended:
The metrics are measured from the corresponding x-height. And measuring from the small cap hight is not good. I’ll fix this. So the outlines didn’t move, just the frame of reverence that is used to measure the sidebearings.
Please check the vertical metrics settings in the masters if everything is correct. There should be an entry like this:
Set the file to “Version 3” in Font Info > Others, otherwise it will write a Glyphs 2 file and that roundtrips that metrics to the smallCapHeight custom parameter.