one Mac downloads; the other doesn't

[Mr Downtown]

I have a Mac Mini and a MacBook Air sitting side-by-side, connected to the same Wi-Fi. Both using Chrome; plenty of HD space. I visit the same website (https://ngmdb.usgs.gov/topoview) and try to download a half-dozen maps. The Mini proceeds just fine; the MBA eventually shows Failed-File incomplete. Downloads from other websites seem to work fine.

What should I check on the MBA?