I would like to have either a keyboard shortcut or preferably another button at the top of the window which would toggle “Show Image”. I believe this would be more efficient than the way it is done now.
You can add your own shortcuts via System Preferences > Keyboard > Shortcuts > Application Shortcuts.
Thanks, Rainer; that works for the most part. Apparently the System reserves Command-Option-Letter for itself because it forced my first attempt to Command-Shift-Option-Letter which is the shortcut for Add Image.
Control-Option-Letter works though, so for the time being all is well. Still hope for a button someday.
There will never be a button for something like this. If I would add a button for every function, Glyphs would look like the word processor of a certain big software company very soon. And nobody wants that.