NeoVim use 0.5-1 sec to go from insert to normal mode IF in tmux, not otherwise.

I use Alacritty with WSL (Debian), and have tested in the following ways.

Tested if it was NeoVim plugins

NeoVim started with no plugins: nvim -u NONE

Use settings to lessen load on tmux / config tmux for performance

Some options I saw could possibly slow down tmux;

set -g mouse offset -g status-interval 60set-option -g history-limit 10000

Used several terminal emulators to test it was not the emulator or WSL

Used PowerShell, Git Bash and Alacritty, without tmux.

Results

I combined these, so I used a performant tmux config, with several emulators, all in WSL, with a no-plugin NeoVim, and the only time it was sluggish to go from insert to normal mode was when I used tmux. I thought maybe it is because tmux is using the escape key, but I use Ctrl+Space and not what was talked about here: https://superuser.com/a/1343036/1763274

Thanks for reading!