We used to run terminal in browser using https://github.com/yudai/gotty and the entire dev team remapped their Ctrl+w to Ctrl+`. We did frontend and backend development with this setup almost for 1.5 years. Muscles memory and till this date, always have the fear if my actual terminal will get closed if I use Ctlr+w :P

Which is why macOS command key is such an undervalued nicety. One key for GUI stuff, one for command-line stuff.

You can use ctrl+shift+t to open the recently closed tab again.

hello, creator here, sorry about that. In this case you can click again on the "Open the Server Terminal in a New Window" button

It would be cool if we could SSH into the temporary host (I'm guessing these hosts currently aren't internet connected to avoid abuse so might not be possible or require some super careful firewalling)

Hello, SadServers guy here. Free VMs are sandboxed (no way in or out other than coming in through the proxy) for security reasons. Paid accounts have VMs with internet access and SSH access (and your pub key is added to all VMs for convenience)

I feel your pain - bites me from time to time, especially in KVM ;)