Easy to reproduce. Visit the site. Choose any non-default layer. Reload page.
It's worth noting that on some level the site thinks the "Reading Order" layer is active when you navigate directly to that link above. (same for other non-default layers) The "eyeball" icon suggests that "Series" is active, and the chart appears with "Series" active. But oddly, if you try clicking on the "Reading Order" eyeball it doesn't change layers to "Reading Order." Any of the other layers will work though. So it's as if the site thinks you have "Reading Order" selected and won't let you toggle it on.
There's a bug with URLs which specify a layer besides the default (series).
For example: https://paleocrafter.github.io/reading-order/#/?layer=reading-order should open the page with the "Reading Order" layer active. Instead it just opens with the default layer, "Series", active.
Easy to reproduce. Visit the site. Choose any non-default layer. Reload page.
It's worth noting that on some level the site thinks the "Reading Order" layer is active when you navigate directly to that link above. (same for other non-default layers) The "eyeball" icon suggests that "Series" is active, and the chart appears with "Series" active. But oddly, if you try clicking on the "Reading Order" eyeball it doesn't change layers to "Reading Order." Any of the other layers will work though. So it's as if the site thinks you have "Reading Order" selected and won't let you toggle it on.