Config polish
Your config lives at ~/.config/zellij/config.kdl (macOS: under the Application Support path). You don't write it from scratch: zellij setup --dump-config prints the full default config, which you redirect to a file and edit down. That dump is also the authoritative source for every default keybinding, the ground truth behind this whole course.
Most options you'll never touch. A handful are worth setting deliberately: which layout to boot, your theme, the shell new panes use, and whether the mouse is captured. Everything is a top-level line in config.kdl.
Try it yourself
Create your config from the dump
Get a real config file in place and set one option.
Tick every step to confirm you did it.
The one command to remember
This command is the source of truth for everything.
What command prints Zellij's complete current default config and keybindings?