this is done in the `needsbuild` hook; the updated PO files must
then be put under version control
-2. trigger a refresh of the corresponding HTML slave pages; this can
- be implemented by making any "slave" page depend on the
- corresponding "master" page. The `add_depends` function can achieve
- this, if used in a **FIXME** hook.
+2. trigger a refresh of the corresponding HTML slave pages: this is
+ achieved by making any "slave" page dependent on the corresponding
+ "master" page, in the `needsbuild` hook.
Also, when the plugin has just been enabled, all the needed POT and PO
files have to be created.