I've not been able to find the crash you are getting but I've added some quick crash logging (version 1.14.1). The desktop versions should create a "crash.log" file when they crash. The browser version will show a popup with the log.
If the game crashes for you again, could you please post the content of the file /popup? It should help me to find the cause of the crash.
Hey there! I'm giving the new update a spin, and I just had an "aha!" moment. Turns out, the app save works perfectly fine without needing to copy the game over the old files. Maybe it was crashing before because I was unnecessarily copying it over, thinking I had to do that to keep my progress.
Good news is, the app feels way more stable now and those weird lag spikes seem to be gone! Now that I know the save is tucked away in appdata, I'll just delete the old folder instead of overwriting it.
if I find any crashes will report back.