Add alignment buttons to the print dialogue.

Some images may have a physical dimension specified.
This should at least be honoured during print, maybe even on display.

Optional (opt-in) side-pane ("_Property pane") with image properties (accelerator: F9)

Optional (opt-in) bottom-pane ("Image _collection") with image thumbnails (accelerator: Control+F9)
	The bottom-pane shall support:
	*	drag and drop to reorder
	*	drag to another application to drop the file by path there
	*	drop form another application to add the image to the collection
	*	right-clicking on a thumbnail and "_Remove from collection" (icon: edit-delete)

Automatically go to next picture

Animation support

Preferences for transparency

Preferences for changling GDK_INTERP_BILINEAR

Fix "GFileInfo created without standard::is-hidden" error message

Fix "GFileInfo created without standard::is-backup" error message

Add support for farbfeld

Add support for lss16

Add support for pam (portable anymap)

Colour space support