Pairs with the click paint-settle fix: even with that, a thread builder
that clicks "Add post" can race a misbehaving handler that closes the
parent modal instead of mounting the next textbox. To make that case
observable instead of silently corrupting the next inserttext, you can
now write:
click @add-post
wait .modal --gone --timeout 2000 # asserts modal stays mounted
inserttext "tweet 3"
If the modal vanished, `wait --gone` succeeds — flip the assertion to
`wait .modal` (default visible) to fail-fast on disappearance.
Implementation just sets `state: "detached"` (or "hidden") on the wait
command — daemon-side `wait_for_selector` already supported these
states; only the CLI parser was missing the user-facing flag.
Also accepts `--detached` as alias for `--gone` to match the daemon's
internal vocabulary.