Topics let you send a single notification to many users who have subscribed to a named topic. Topics are managed through the Firebase Cloud Messaging topic subscription API.
Topics List
Click Messaging → Topics in the sidebar to see all configured topics.

Creating a Topic
Click New Topic
On the Topics page, click + New Topic.
Enter a topic name
Give the topic a descriptive name (e.g., breaking-news, promotions). Topic names are case-sensitive and must not contain spaces.
Save
Click Save. The topic is created and ready to be used in Campaigns.
Sending to a Topic
When creating a Campaign, select Topic as the target and choose the topic from the list. All users subscribed to the topic will receive the notification.
Note:
User subscription to topics is managed by your app code using the FCM SDK. Firepanel manages the topics list and sending, but does not control who subscribes to a topic.