I just applyed a correction of PO with ' for Rennes 2 University.Thinking of it, the best solution is to use ' instead of a quote : translate "Today" into "Aujourd'hui". It is good for both HTML and Javascript.Have you tried? Does it work? It also could be done automatically when installing translation files: translate install fr-FR Translated string could be modified on the fly, when translating JavaScript string. It would avoid asking translators to encode '