Is anybody else having problems with undo not working in 1.3.20? I am restarting Glyphs at least once an hour because of this. In single master fonts undo just stops working. In fonts with multiple masters Glyphs seems to lose track of the layer changes apply to, sometimes changing the wrong layer, sometimes not working, and eventually crashes.
I found some issues with guidelines breaking the undo.
And do you have manual hints in your glyphs?
And it should break the undo only for a certain glyph.
I use guidelines extensively.