 "true");

    const dfnPanel = genDfnPanel(dfn, dfn.panelData);

    // Give the dfn a unique tabindex, and then
    // give all the tabbable panel bits successive indexes.
    let tabIndex = 100;
    dfn.tabIndex = tabIndex++;
    const tabbable = dfnPanel.querySelectorAll(":is(a, button)");
    for (const el of tabbable) {
        el.tabIndex = tabIndex++;
    }

    append(document.body, dfnPanel);
    positionDfnPanel(dfnPanel);
}

function positionDfnPanel(dfnPanel) {
    const dfn = dfnPanel.dfn;
   