Function unsubscribe 

pub(crate) fn unsubscribe(
    qt: &CxxQtThread<Sioul>,
    shared: &Arc<Shared>,
    config: &Config,
    triaged: Option<Triaged>,
) -> String

One click on “Unsubscribe”: one click (RFC 8058) or a message to the list waits ten seconds with “Undo”, as sending does; a list that takes it only on its web page has the page returned, to open in the browser, at once. What cannot be done is said in the status line, the button’s tip.