Formiko have Vim editor support aka formiko-vim command. This run Vim editor in GtkSocket. At this
moment, this socket work only on X11 backend, so this is not work on Wayland yet.
It would be much better to use Neovim and its msgpack-rpc API (Python client). It would avoid the use of the X11-only GtkSocket and could provide much better Vim integration.
README says:
It would be much better to use Neovim and its msgpack-rpc API (Python client). It would avoid the use of the X11-only GtkSocket and could provide much better Vim integration.