Match aspect ratios or preserve order (retired in 1.3.5)

This setting was retired in version 1.3.5 and there is nothing to configure. Every project now uses balanced placement, which weighs aspect ratio first and uses the order you selected in the photo library as the tiebreaker - what the recommended setting did anyway. The tutorial clip below still shows the old Settings panel.

Starts at 54:08 in the full tutorialWatch on YouTube