The web picker opened on the Sessions grid, at true size, once per candidate tick. Everything except the tick is the shipped picker: the Export menu's box and rows, the role toggle, and the split person badge, with CSS inlined from the tree. The picker opens with focus on the ticked row, so each frame shows the tick on that row's grey.
Each tick is rasterised at its true rendered size on this screen (device pixels), then enlarged without smoothing, so the antialiasing is real, not redrawn. Follows the appearance and type switches.