Ghostty has a shortcut “Ctrl+,” to open the configuration file, under ChromeOS Flex, this short does nothing.
To find out which application opens the configuration file, run the following command:
xdg-open ~/.config/ghostty/config
It opens the file with Emacs in terminal mode on my machine, and setting it to open with the normal Emacs solves the issue.
xdg-mime default emacs.desktop text/plain
Linux under ChromeOS runs inside a container sandbox, it has many quirks that are unique to this environment, so far nothing has been a deal-breaker yet.