I have an C++ application using
gtk_file_chooser_dialog_new() to open files. The generated dialog shows the folder and contained files without the thumbnails in the leftmost column (dummy black thumbnails do appear). The thumbnails in
/home/$USER/.cache/thumbnails are missing and are not being generated. If I then open the same folder with Nautilus, the thumbnails are generated as expected. If I then go back to the application using
gtk_file_chooser_dialog_new(), the thumbnails now appear correctly.
gtk_file_chooser depend on Nautilus to preload the thumbnails? What am I missing here?
UPDATE: Every Gnome app that opens files has the same problem. If the thumbnail cache does not have the thumbnails, the app's open file dialog displays dummy black thumbnails. Only if you visit the same folder with Nautilus will the thumbnails be created. Is this a Gnome bug or have I got some installation issue?