Ah the guillemetright is made of 2 guilsinglright! There we go, if I decompose the guillmetright, then when I decompose the flipped guillemetright in guillemetleft it doens’t change. Still doesn’t explain why the skew flips from negative to positive and vice versa every time I save
Glyphs 3 stores the transformation as scale, rotation, skew separately. Glyphs 2 stores the combined transformation matrix. So reading/writing Glyphs 2 files needs to convert back and forth. And that horizontal flip and skew is difficult to recover. Even the best algorithm I could find struggles with this.
So I recommend to, instead of horizontal flip and skew, rotate 180°. Automatic alignment can help with positioning.