Hi, you got it right, normally modern browsers sandboxing web content, isolating it and preventing crashes from affecting your OS.
If web game can crashes you desktop, it most likely to be some gpu incompatibility.
The next update (Chapter 2, releasing Jan 13) includes patches for this, though I can’t guarantee it’ll cover every gpu variation.
Save import/export isn’t ready yet, and unfortunately the chapter 2 update will reset saves due to significant backend changes.
I’m really sorry for the bad experiences and inconvenience >_<.