.pptx

PowerPoint Open XML

Handled by macOS itself

Format facts

MIME type: application/vnd.openxmlformats-officedocument.presentationml.presentation
Apple UTI: org.openxmlformats.presentationml.presentation
Stock Quick Look: macOS renders a preview
Planned approach (census): native-sufficient
Icon hint: unknown
Prevalence: universal

macOS previews PowerPoint natively

Gotchas: slide count in presentation.xml