Currently, Glyphs offers ⌘W “Close” which closes the edit view (if in edit view) or the window (if in font view).
I would like to propose an additional “Close Window” command (e.g. ⇧⌘W) to close the window from any view (edit or font). [Edit: I’ve just seen that this shortcut is bound to “Close Tab” by default; maybe ⌃⌘W would work, too.]
TextMate does this with the naming and shortcuts as detailed above:
I think View → Close Tab is redundant since File → Close does more or less the same, so the plugin removes the ⇧⌘W shortcut from the Close Tab command and uses it for the new Close Window menu item.
Ack! This really should be labeled close window without warning. I just lost some work because I had installed this when I first started using Glyphs to try it and then forgot about it. Then I tried to close a tab and blam.
Sorry! This is a limitation of providing the feature as a plugin. I’ve since joined the Glyphs team and you will see the “Close Window” feature built into a future version of Glyphs in such a way where you will get a proper warning before any unsaved changes are lost.