Linguist doesn't display id for id-based translations

Consider the following source file with id-based translations.

int myFunction()
{
    //% "%n fooish bar(s) found.\n"
    //% "Do you want to continue?"
    QString text = qtTrId("qtn_foo_bar", n);
}

If we create a .ts file from it, we can see the translation ID only in the source window.

$ lupdate foo.cpp -ts foo_de.ts 

Now, if the user disables locations (for example, to work around QTBUG-127139), there's no way to determine the ID for a translation anymore:

$ lupdate foo.cpp -ts foo_de.ts -locations none

Since id-based TS files don't contain context information, Linguist makes the translation task unnecessary hard by omitting the display of the ID.

Original forum post: https://forum.qt.io/topic/158298/linguist-not-showing-id-in-id-based-mode/5