Oops! I like to use the back button too. While implementing the distributable link feature, I overlooked that this is breaking the back button behaviour.
Thanks for pointing this out! I have pushed a fix for it just now. Please hard-refresh the page (ctrl+F5, cmd+shift+r, etc.) and let me know if you still see issues.
The GitHub link is helpful, it might be useful to include what each command does at the bottom of the page so users don’t have to go to the GitHub page to figure it out
It stores the program in the URL bar so you can send other people links to your drawing.
Sure, but it also added 50 entries to my browsing history. You can use the browser history API to only replace the state instead of pushing new states on.