Basically it is enough to turn on Guest Cache (Admin CP -> vBET Cache -> Guest Cache -> Use Full File Cache For Guests).
When Guest Cache is on, then showing translated URL's under the flags is enabled. For performance reasons it works only for guests. It is not necessary for logged in users to see translated URL's under the flags - such user mostly is already on translated page before log in, or do not need translation at all. The feature is mostly for search engines spiders which are crawling any existing link on page. So now Google will not complain about lot of redirects.
And because showing translated URL's under the flags it is integrated with Guest Cache it will not give any performance penalties, since additional queries to database will be made very rare (only when refreshing cache).
Please note that there can be several situations when URL under the flag is not translated and redirection still happens:
- Always for logged in users (as described before it is not necessary to waist resources)
- When URL is not translated yet (for performance reasons do not ask for all flags translations immediately, but after first redirect translation will be available in database cache)
- When URL is translated already, but also page is already cached in Guest Cache with no translation (this is related to previous point, but as soon as Guest Cache expires your guests will see translated URLs under those flags which are already translated)
So assuming: it is working for guests only, with delayed requests for translation - for performance reasons.