Server-rendered markup with the justified container class already in place, Unsplash thumbnails held back one after another by the dev server, and the script delayed so the pre-init window is visible. The grid must never be seen unorganized: placeholders fill the rows at init and thumbnails fade in row by row as they arrive.
default (thumbs held 400ms apart by the dev server, 1500ms script delay) thumbs 1s apart per-image reveal 4s script delay without the markup class (the old flash) real network speed (cache-busted) small thumbs, real speed, no delay back to the scenarios