I just purchased Glyphs, and I completed the designs of /A/ through /R/. For some reason, the ‘Select Sample Text…’ command in Edit is not enabled. I saved, I closed and re-opened the app, and I searched the manual and the forum for reasons why this would be disabled. I exported the font as an OpenType file and the font worked in my text editor.
What are the conditions that need to be true in order for that menu item to be enabled?