What Happens When a Display Loses Its Internet Connection
A LobbyFlight display keeps no offline copy of your flight data — here is what viewers actually see during an outage, and where you can see it in the portal.
What Happens When a Display Loses Its Internet Connection
The short answer is that a LobbyFlight display does not keep working offline. There is no offline store, no downloaded copy of your flight board, and nothing that keeps the screen useful once the network is gone. This article explains exactly what a guest in the lobby sees during an outage, why the product is built that way, how fresh the data is when everything is working, and where in the portal you can tell that a screen has dropped off.
What the screen shows during an outage
Two things happen, and they happen at different moments.
The moment the browser notices that it has no connection, an orange badge appears in the top corner of the display reading Offline Mode. This comes straight from the browser's own online and offline events, so it is close to instant. The badge is currently rendered in English on every display, regardless of the language the rest of the board is set to.
The flight board itself only reacts at its next scheduled refresh. Until that moment the flights you can see are simply the ones already drawn on the screen. When the refresh fails, the board does not keep showing them — it replaces the whole list with a red panel reading Connection error and Unable to load, plus a Try again button. So the outage is visible to anyone standing in front of the screen, at the latest one refresh interval after the connection drops.
The clock and date in the header keep ticking, because they run entirely in the browser and need no network. Your logo, colours and layout also stay on screen — but only because the page is still loaded. If anything reloads that page while the network is down, nothing comes back at all.
Why there is no offline cache
This is a deliberate design decision rather than a missing feature. A departure board that confidently shows stale times is worse than one that admits it has no data: a guest who reads a cached 14:35 departure and leaves for the airport accordingly is worse off than a guest who sees an error and asks the front desk. The same reasoning is written into the one service worker the product does ship — the guest companion service worker, which exists only to receive push notifications and explicitly performs no offline caching.
For the lobby display there is no service worker at all. Nothing intercepts requests, nothing is stored in Cache Storage, and there is no cached copy for you to inspect, warm up, or clear.
How fresh the data is when the network is fine
There is one real caching layer, and it lives on our servers rather than on your screen. Flight data is stored server-side with a lifetime that depends on your plan:
That interval is the only lever you have over data freshness, and you change it by changing plan — there is no cache duration setting anywhere in the portal. See Understanding Your Subscription if you want to compare what each tier includes.
Weather is fetched with a 30-minute lifetime and may be served for up to an hour longer while a fresh copy is fetched in the background. Your display configuration — branding, rotation, selected content — is re-fetched every 20 seconds, which is why changes you make in the portal appear on the screen almost immediately.
One more server-side fallback is worth knowing about: if our flight data provider is unreachable, the server can fall back to a copy of the last successful flight list kept for 24 hours, so a provider hiccup does not empty your board. This only helps when the provider is down and your display is online. It does nothing for an outage in your own building, because the display cannot reach our servers at all in that case.
Where you see that a display has gone offline
Do not go looking in browser developer tools. Every display sends a heartbeat to LobbyFlight every five minutes, and that heartbeat is what the portal uses to judge whether a screen is alive.
A display is treated as offline once more than 12 minutes have passed without a heartbeat. Twelve minutes is two missed beats plus a little slack — a shorter threshold would report every brief stutter as an outage, while a genuinely dark screen is still flagged within about a quarter of an hour.
You can see the result in two places. Under Displays in the portal, each screen carries a status and a last-seen time, with offline screens sorted to the top of the list. On the dashboard, offline screens are counted and each one raises a warning reading Display "…" appears offline (last seen: …).
Note that a screen you switched off yourself in the portal is marked inactive rather than offline and raises no warning, and a screen that has been created but never opened is treated as an unfinished setup step rather than a fault.
Getting a display back
When the connection returns, the browser fires its online event and the orange badge disappears on its own. The flight board, however, does not repaint immediately — it waits for its next scheduled refresh, or for someone to press Try again on the red error panel. Whichever comes first, no manual intervention is needed beyond that.
If a screen is stuck showing the error long after the network is back, reload the display URL. That is the whole of the "clear the cache" procedure: since nothing is stored locally, a reload gets you a completely fresh page. The same reload happens automatically whenever you change display settings in the portal, which is how those changes reach a screen you cannot physically touch.
If a display stays offline while other devices on the same network are fine, the cause is almost always the network path rather than the display itself. Network Requirements and Firewall Configuration lists the domains and ports that have to be reachable.