LOL!
After escalating this to a top exec at Tripadvisor, finally the support crew got back to my ticket!
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"Customer Support (David) (TripAdvisor Support)
Dec 7, 22:01 GMT
Hello Jan,
Thank you for contacting TripAdvisor.
We'd like to thank you for being an active contributor of our travel community.
In regards to the Pontus in the Air restaurant listing, there has been a misinterpretation of our guidelines which resulted in the removal of the listing. TripAdvisor does list certain restaurants and attractions which are after security in specific airports, Stockholm Arlanda being one of them.
To correct this, we have re-established the Pontus in the Air restaurant listing, which will go live on our website in 48 hours. In addition, we've marked this restaurant as being after security. This tag will be visible on the listing to ensure traveler's are aware of this restaurant's location.
We will follow up with the agents who at the time were not able to correctly interpret the listing guidelines to prevent this from happening in the future. We apologize for any inconveniences caused and once again thank you for your contributions."
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What still needs to be clarified:
1. Can TA please rewrite the listing policy, to avoid future overzealous staff from deleting again?
2. As a user, how do I know WHICH establishments at WHICH airports are legit, if I want to review a new restaurant that is not yet listed?
3. Is there any way for a user to flag a listing as "past security"? Or what is the correct procedure to add this tag if it is missing from a listing?