> For the complete documentation index, see [llms.txt](https://en.help.firstline.cc/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://en.help.firstline.cc/guide/issue/network-offline-reminder.md). # Network offline reminder When FIRST LINE detects that the connection between the browser and the live service has been interrupted or reconnected, the system will display a network offline reminder. This article explains in plain language why the live connection may be briefly interrupted, why other websites can still be opened, and how to determine and handle the reminder when it appears. Features such as new messages, incoming call notifications, and service status updates in FIRST LINE require the browser to stay continuously connected to the live service. When this connection is interrupted, or when it is being re-established after an interruption, FIRST LINE will display a "network offline reminder" to let you know that real-time features may be affected during this period. {% hint style="info" %} **First, the conclusion: an offline reminder does not mean "the whole computer has no internet," nor can it be used alone to determine that the problem must be with the user's network or FIRST LINE.** What it can confirm is this: at a certain point in time, the previously continuous connection between the browser and the FIRST LINE live service was interrupted, or was in the process of being re-established. {% endhint %} ## Why does the live service need to be "always connected"? A typical website is more like "fetch data when needed." For example, when you open an article, the browser sends a request and retrieves the content; once that transfer is complete, you can continue reading. Customer service systems are different. New messages, incoming calls, or status changes can happen at any time, and the server needs to actively notify the browser when events occur, so this kind of real-time web application usually uses **WebSocket or other persistent connection technologies**. You can think of it as two different ways of staying in touch: | Standard web connection | Real-time connection | | ------------------------------------------------------------------------- | ------------------------------------------------------------------------------ | | Like calling to ask only when you need something | Like a call that stays connected the whole time | | Create a request each time data is needed | The browser and service keep the connection continuously open | | After a brief interruption, the next request may simply be re-established | Once an existing connection is broken, it needs to be detected and reconnected | | Suitable for articles and general page content | Suitable for chat, notifications, real-time status, and more | [MDN Web Docs WebSocket documentation](https://developer.mozilla.org/zh-TW/docs/Web/API/WebSockets_API)also describes WebSocket as bidirectional interactive communication between the browser and server, allowing both sides to keep exchanging data over an existing connection without the browser constantly having to ask the server again. ## Even when the network is normal, a persistent connection can still be briefly interrupted This is not a problem unique to FIRST LINE, but something that real-time network services must handle. For example [Socket.IO](https://socket.io/) is a widely used real-time communication technology, and its official documentation explicitly lists "automatic reconnection after connection loss" as one of its basic capabilities. This means that real-time applications are designed from the start not to assume that a connection will never be interrupted. Cloudflare, the network infrastructure provider's [WebSocket official documentation](https://developers.cloudflare.com/network/websockets/) also recommends implementing keepalive for long-lived connections and explains that connections may end due to timeouts or infrastructure restarts. {% hint style="success" %} **When FIRST LINE shows an offline reminder, it is surfacing the real-time connection status that was originally hidden from the user.** If the real-time connection has already been interrupted but the screen shows no reminder at all, the agent may still think they are normally waiting for new messages or calls. The purpose of actively displaying connection status is to let you know early whether the current real-time capability can be trusted. {% endhint %} ## Why can Google and YouTube open, but FIRST LINE still shows offline? This is the easiest point to misunderstand. **"Other websites open" can prove that the internet is still available right now, but it cannot prove that every previously established real-time connection has not been interrupted.** For example: 1. Your Wi‑Fi briefly went down for a few seconds at 10:00:00. 2. The real-time connection that FIRST LINE had been maintaining was therefore disconnected. 3. The network came back at 10:00:05. 4. At 10:00:10, you opened Google, and the browser established a new network request, so the website opened normally. 5. At the same time, FIRST LINE will also try to re-establish the real-time connection and display the status of having been offline or reconnecting. So "I can browse other websites right now" and "did the real-time connection just break earlier" are two different questions. Similar situations can also happen when: * Wi‑Fi switches between access points. * The VPN briefly reconnects. * Corporate proxies, firewalls, or other network devices re-establish the connection. * The computer wakes from sleep or power-saving mode. * The browser pauses background tabs that have not been used for a long time. ## Reminder status you may see ### Currently offline This means the browser is currently unable to maintain a connection with some FIRST LINE live services. During this period, the following may be affected: * Real-time display of new messages. * Incoming call notifications. * Help desk status updates. * Other features that require a real-time connection. The system reminder may show the type of service currently interrupted, making it easier to judge the scope of the impact.

Real-time web services usually detect connection status to avoid users continuing to use interrupted real-time features without knowing it.

### Previously interrupted, but now restored This means there was a brief disconnection just now, and the browser has re-established the connection. If it only happens occasionally and messages, calls, and status updates work normally after recovery, you can continue using it and observe. If it happens repeatedly within the same day, it means the real-time connection environment is not stable enough, and it is recommended to further check the network, VPN, device, and browser settings.
## What may cause a real-time connection to drop? Common causes include: * **Wi‑Fi fluctuations**: brief signal instability, access point switching, or wireless interference. * **VPN**: VPN reconnection, route switching, or connection timeout. * **Corporate network equipment**: proxies, firewalls, and security devices may re-establish or terminate long-lived connections. * **Device sleep or power saving**: the computer pauses background network activity and needs to reconnect after waking. * **Browser background energy saving**: tabs that have not been used for a long time may be slowed down or put to sleep. * **Browser extensions / security software**: some extensions or protection software may interfere with the connection. * **Server-side or network path events**: a brief switch in the live service itself, cloud services, or intermediate network devices may also interrupt existing connections. {% hint style="warning" %} **The offline reminder itself can only indicate that "the real-time connection was interrupted" and cannot by itself determine which side is responsible.** If it only happens repeatedly on one computer or one corporate network, and it works normally when using another network, it is worth checking the local machine or enterprise network; if multiple users at different locations and on different networks experience it at the same time, then you should further verify whether there is an issue with a shared service or network path. {% endhint %} ## Are latency, lag, and offline the same? Not exactly. * **Latency**: data is still being transmitted, just more slowly. * **Packet loss / poor network quality**: some data transmissions fail, which may cause choppy calls or delayed messages. * **Real-time connection interrupted**: the browser can no longer continue using the original persistent connection and needs to re-establish it. Therefore, "choppy call audio" will not necessarily trigger an offline reminder; conversely, quickly reconnecting after a brief offline period does not mean all normal web pages will show errors at the same time. ## What should I do after seeing the reminder? {% stepper %} {% step %} ### First check whether it has already recovered If the reminder shows that it has reconnected, first confirm whether FIRST LINE can normally receive new messages, update status, or receive call notifications. If the functions have recovered, you can continue using it and observe whether it happens again. {% endstep %} {% step %} ### Confirm whether the general network is working Open other websites to confirm whether you can still access the internet. If other websites also do not work, first address local Wi‑Fi, wired network, VPN, or corporate network issues. If other websites work normally, do not immediately rule out network factors, because the existing real-time connection may still have been briefly interrupted. {% endstep %} {% step %} ### Refresh FIRST LINE If the general network is normal but FIRST LINE real-time features still have not recovered, you can refresh the page so the browser re-establishes the required connection. {% endstep %} {% step %} ### If it happens repeatedly, record the time If the offline/reconnect reminder appears several times in one day, it is recommended to record the approximate times, such as "10:15, 11:42, 14:05." With clear timestamps, IT or FIRST LINE can more easily compare VPN, firewall, network device, and server-side logs. {% endstep %} {% step %} ### Cross-test in another environment If convenient, you can try one of these methods: * Use a mobile hotspot on the same computer. * Use another computer on the same corporate network. * Use Incognito mode. * Switch to another supported browser. The purpose of cross-testing is not to "prove whose problem it is," but to quickly narrow down the scope of the issue. {% endstep %} {% endstepper %} ## How can the chance of connection interruption be reduced? ### Prefer a stable network If your work includes real-time messaging or phone services and the environment allows it, it is recommended to prioritize a stable wired network (Ethernet). Wi‑Fi can certainly be used, but wireless interference, distance, and access point switching add more factors that may cause momentary fluctuations than wired networks do. ### Avoid putting the work device to sleep during service hours If the computer enters sleep or deep power-saving mode, the browser and network connection may pause. If the company has unified screen-lock, power-saving, or device management policies, you can ask internal IT to confirm whether background connections will be interrupted. ### Check the browser's sleeping tabs / memory saver settings Browsers such as Chrome and Edge may apply memory saver or sleep mechanisms to tabs that have not been used for a long time. If FIRST LINE often reconnects only after you switch back to the tab, you can check whether the browser has related energy-saving settings and, if necessary, add FIRST LINE to the exception list. * [Chrome Memory Saver mode documentation](https://support.google.com/chrome/answer/12929150?hl=zh-Hant) * [Microsoft Edge official documentation](https://support.microsoft.com/zh-tw/microsoft-edge) ## What situations are more like a company network or device issue? The following situations are recommended to be checked first by enterprise IT: * It only happens on the corporate network, but works normally when using a mobile hotspot. * The problem only occurs on a specific computer. * The problem only appears when connected to the VPN. * Multiple colleagues in the same office or on the same network experience it at the same time. * It is easy to disconnect at a fixed time every day, which may be related to network equipment, VPN, or security policies. * The company has proxy, firewall, security software, or device management policies that manage long-lived connections. {% hint style="info" %} It is not recommended that ordinary users broadly disable firewalls or security software on their own just to troubleshoot the issue. If you suspect that corporate network policies are affecting real-time connections, please have IT personnel verify it. {% endhint %} ## When should you contact FIRST LINE? The following situations are recommended for contacting FIRST LINE for assistance: * The general network is normal, but FIRST LINE real-time features cannot recover for a long time. * It still shows offline after refreshing. * Multiple users on different networks and at different locations experience it at around the same time. * The problem happens repeatedly, and basic network and browser cross-tests have already been completed. It is recommended to provide: 1. **Time of occurrence**: the date and as precise a time as possible. 2. **Scope of impact**: only you, some colleagues, or all users. 3. **Actual symptoms**: for example, "the offline reminder does not go away," "messages are not updated in real time," or "no incoming call notification." 4. **Usage environment**: browser, operating system, and whether VPN is used. 5. **Network used**: corporate wired, corporate Wi‑Fi, home network, or mobile hotspot. 6. **Cross-test results**: whether another browser, Incognito mode, or another network works normally. This information can help determine more quickly whether the issue is more likely with the personal device, corporate network, shared network path, or FIRST LINE live service. ## Further reading: this is not a FIRST LINE-specific technical issue If you want to learn more about real-time connections, you can refer to the following public technical documents: * [MDN Web Docs: WebSocket API](https://developer.mozilla.org/zh-TW/docs/Web/API/WebSockets_API)- explains how browsers maintain bidirectional communication with servers through WebSocket. * [Socket.IO official website](https://socket.io/)- introduces real-time bidirectional communication and the design for automatic reconnection after connection loss. * [Cloudflare: WebSockets](https://developers.cloudflare.com/network/websockets/)- explains how network infrastructure handles long-lived WebSocket connections, keepalive, and connection timeouts. The common concept behind these mechanisms is:**Real-time connections can be very stable, but they cannot be assumed to never break, so mature real-time services detect connection status and reconnect when necessary.**