Ajuda del LibreOffice 24.8
You can quickly exit manual formatting by pressing CommandCtrl+Shift+X. For example, if you have pressed CommandCtrl+B to apply the bold typeface to the text that you type, press CommandCtrl+Shift+X to return to the default character format of the paragraph.
Per reinicialitzar tota la formatació directa d'un text, seleccioneu el text i trieu l'orde de menú Format - Neteja el format directe.