At the most recent just released glyphs 3 version 3.0.4 (3105), at a particular large zoom while editing a long string of glyphs, the zoom jumps to the previous line of glyphs instead of staying on the current glyph in the center of the screen and then on the next zoom in the same direction of zoom, it jumps back to the glyph that you started at. Above and below this discontinuity it zooms fine but at this one large zoom area it is erratic jumping back and forth between lines of glyphs. I just tested it again and it jumps twice between glyph lines, zoom OK at glyphs smaller than zoom box, away to different line, back to original line, away to different line, back to original line, zoom OK at glyphs larger than zoom box. The zoom bug happens as you approach the glyph filling the window box so maybe there is some interaction with the calculations of the window box center or edges or something so it works fine when the glyph is smaller than the window box and larger than the window box, but has a bug when the glyph size is about similar to the window box?
Can you send me a screen recording and the file you are using?
Sorry I didn’t wait, but it fixed itself after awhile. Maybe after updating to the latest version and automatically reopening, there was something in active memory that took the program some time to recalculate and update or something like that, but now it works fine again. So I can’t replicate the problem.