Comment by leeoniya

related: i had to jump through the Date hoops recently (again) when rewriting uPlot's DST and timezone handling, but i'm pretty happy with the result that avoided much complexity, performance loss, and adding a dependency: https://github.com/leeoniya/uPlot/pull/1072

fun demos: https://leeoniya.github.io/uPlot/demos/timezones-dst.html