ction toggleDfnPanel(dfn) {
    if(dfn.dfnPanel) {
        hideDfnPanel(dfn);
    } else {
        showDfnPanel(dfn);
    }
}

function insertDfnPopupAction(dfn) {
    dfn.setAttribute('role', 'button');
    dfn.setAttribute('aria-expanded', 'false')
    dfn.tabIndex = 0;
    dfn.classList.add('has-dfn-panel');
    dfn.addEventListener('click', (event) => {
        toggleDfnPanel(dfn);
        event.stopPropagation();
    });
    dfn.addEventListener('keypress', (event) => {
        const kc = event.keyCode