Move the avatar icon generation code from mailnag-gnome-shell (aggregate-avatars.vala) to a mailnag plugin.
The generated icons should be stored in a volatile location like /run/user//mailnag/avatars.
Icons should have the name of the associated email address.
Benefits:
The mailnag-gnome-shell extension published to extensions.gnome.org currently does not support avatar icons (because uploading binaries like aggregate-avatars is not allowed). This would change if mailnag itself would provide avatar icons.
The libnotify plugin could show those icons in a notification.
Other extensions/programs could use the generated icons.
mailnag-gnome-shell would be javascript only (no more compilation/installation steps required).
Move the avatar icon generation code from mailnag-gnome-shell (aggregate-avatars.vala) to a mailnag plugin.
Benefits: