Individual challenge completion not saved

I’m not sure if this was an intentional change but it used to work differently before the redesign. When I look at my finished challenges in the curriculum they’re correctly marked as completed, but when I open them my solution is no longer there as the code has been reset.

It used to be very useful to just take a quick look at my solutions to remind myself how certain things worked but now I have to redo each challenge when I open it again. Am I looking at a bug or was this done intentionally to force us to redo our challenges when revisiting them?