I’m used to selecting glyphs in the preview panel by shift + 
over the texts. However, in the vertical text direction, shift + ↓ doesn’t work.
It would also be great if the views could follow the current editing glyph when changing text direction from horizontal to vertical and vice versa. For designing CJK fonts it would be necessary to preview glyphs set in both horizontal and vertical directions, and usually when the text direction is changed, I would be looking at somewhere far away from the glyph that I focused on. It would be great if it can stick to the same glyph that I was looking at.