Group Firebase FCM on Android Device(在 Android 设备上分组 Firebase FCM)

is there anyway to send notification from one device to other device using FCM without Firebase Database?(无论如何，是否可以在没有 Firebase 数据库的情况下使用 FCM 从一台设备向另一台设备发送通知?)

Firebase Cloud Messaging : Expiration of FCM token(Firebase 云消息传递:FCM 令牌过期)

Push Notifications without Firebase Cloud Messaging(没有 Firebase 云消息传递的推送通知)

Firebase Notifications - Invalid reg token, please check token format in Android(Firebase 通知 - 注册令牌无效，请检查 Android 中的令牌格式)

When do fcm refresh tokens created(何时创建 fcm 刷新令牌)

FCM Cannot show pop up when app in the background(当应用程序在后台时，FCM 无法显示弹出窗口)

how to display message of push notification from firebase cloud messaging on textview android(如何在textview android上显示来自firebase云消息的推送通知消息)

How to send push notifications without using Firebase console(如何在不使用 Firebase 控制台的情况下发送推送通知)

How to generate firebase registration token(如何生成 Firebase 注册令牌)

Firebase onMessageReceived not called when app is inactive(应用程序处于非活动状态时未调用 Firebase onMessageReceived)

FCM with ionic 2 in background not working(离子 2 在后台的 FCM 无法正常工作)

Firebase Cloud Messaging token is not generating(Firebase 云消息传递令牌未生成)

How to collapse multiple notifications into a single one using Firebase?(如何使用 Firebase 将多个通知合并为一个?)

FIrebase Cloud Messaging, cannot resolve dependency com.google.firebase:firebase-core:9.0.2(FIrebase 云消息传递，无法解析依赖项 com.google.firebase:firebase-core:9.0.2)

Is there any way how to get data from push notification using FirebaseMessagingService in background?(有什么方法可以在后台使用 FirebaseMessagingService 从推送通知中获取数据?)

Android - GCM server key is not working with Urban Airship(Android - GCM 服务器密钥不适用于 Urban Airship)

How is Android Firebase messaging SDK secure against Intent spoofing?(Android Firebase 消息传递 SDK 如何防止 Intent 欺骗?)

Firebase notification is not working when activity is in background or not(活动是否在后台时，Firebase 通知不起作用)

Want to know how FCM works in below scenarios(想知道 FCM 在以下场景中的工作原理)