I just noticed, from the picture on Digikey, Lepton appears to be one with a shutter, and this covers the lens, so there's no way to grab the lens and turn it for focusing.
Lepton 2 with manual focus, but no shutter
Lepton 2 with shutter, but fixed focus
Lepton 3 with shutter, but fixed focus
I have yet to see a Lepton 3, which actually has manual focus. Does FLIR intend to ever produce such? Or do they feel that such a component would compete too strongly with some of their full-featured thermal imager devices (which cost thousands of dollars), so they intentionally hinder this very powerful component by not letting it have any manual focus?