From my tests it appears that pictures are quietly discarded if the ~/Pictures folder doesn't exist. I think what the app should do is 1. attempt to create the folder, and 2. if that fails, show an actual error instead of just kinda pretending it worked :-D
Hardcoding ~/Pictures is a problem, because the folder name could be different. I think it would be better to use g-get-user-special-dir from glib:
I've pushed a fix that uses
g_get_user_special_dirto the "pictures-fix" branch on my fork.
Merged that change, thanks Benjamin :)