This just happened to me and I didn't see this comment until I refreshed the page :( This is a screenshot of it after it froze. Local browser saves are super simple, you should really consider adding it...
I wanna play mooooore! For the base, it's a little confusing that digging tunnels works differently than in the mine, I was expecting to click and drag to make a line/box. And when the demo ends I want to be able to go back into the mine! This is really fun for some reason.
