They are floating point values. There is going to be some slight drift because you can't store those exact values in a float, only a very close approximation. Anything that rounds it to a couple of decimal places is going to get the original value back in almost every case. Yes, I understand that, ...

After cheking the data, for example if "assembling-machine-3" has a defined collision box in \data\base\prototypes\entity\entities.lua as: collision_box = {{-1.2, -1.2}, {1.2, 1.2}}, And the output in data-raw-dump.json is: "collision_box": [ [ -1.19999999999999996447286321199499...

The output of --dump-data for some values has an excesive number of decimal places. Examples: clickable_label = { type = "label_style", hovered_font_color = { 1, 0.74000000000000003552713678800500929355621337890625, 0.4 }, clicked_font_color = { ["r"] = 0.980000000000000071054273...