In keeping with the pile-of-files theme, OpenDocument stores all slide content in a single big XML file named "content.xml". LibreOffice reads and parses this entire file just to display the first slide. LibreOffice also seems to read all images into memory as well, which makes sense seeing as when the user does "File/Save" it is going to have to write them all back out again, even though none of them changed. The net effect is that start-up is slow. Double-clicking an OpenDocument file brings up a progress bar rather than the first slide. This results in a bad user experience. The situation grows ever more annoying as the document size increases.