function _updateSettings() {
    console.log("_updateSettings()");
    // if using GFM while the adaptive width mode is active, then disable the "break" option.
    var useGFM = PreviewPreferences.useGFM;
    var useAdaptiveWidth = PreviewPreferences.adaptiveWidth;
    var useBreaks = useGFM && !useAdaptiveWidth;
    marked.setOptions({
        breaks: useBreaks,
        gfm: useGFM
    });
    // Re-render 
    _loadDoc(currentDoc);
}