Answer by A248 for How to change default terminal application in Gnome-Shell

I was able to solve this by modifying the GNOME Application in /usr/share/applications/.

1. Find and open the terminal application. For myself it was located at /usr/share/applications/org.gnome.Terminal.desktop
2. Modify uses of "TryExec" and "Exec" to replace gnome-terminal with your terminal emulator of choice.

• For this step, if you want interoperability with update-alternatives, you can replace gnome-terminal with x-terminal-emulator. That way, when you use update-alternatives to change the destination of x-terminal-emulator, the application will update automatically.

3. Restart the terminal

So far this solution has worked quite well for me. It has the caveat that the application will show up as your terminal of choice, rather than GNOME Terminal, on the dock - you will have to observe what I mean for yourself.

In my case, I use alacritty. To enable CTRL+N functionality I had to configure alacritty similarly to here.