In order for users to receive push notifications from a website, they must opt in to join the subscriber base. However, sometimes despite the subscription, messages do not reach intended users. There are many reasons for that. Here are the most important ones.
Push notifications will not be displayed to recipients who have disabled the option to get messages delivered on their device. If they have checked the option to block notifications in the site settings, they will not get any notifications. In this case, such subscribers should be removed from the list. Owing to this, we will be able to assess the actual deliverability rate of messages.
Push notifications are sent to Cloud Manager (e.g. FMC – Firepower Management Center for Chrome) and then delivered to individual browsers. If a user has opted out of receiving push notifications from the browser or has not been using it for a longer period of time, they should be deleted from your subscriber list. Sometimes the opt-out is not updated in Cloud Manager or there is a delay related to the registration token removal from the FMC. In such an event, the notifications receive a valid identifier, even though the messages are not delivered to the recipients.
If subscribers turn on battery saver mode on a computer or mobile device, push notifications may not be delivered to them. In this case, the system stops working, preventing the display of messages on the user’s device.
Browsers make it possible to create multiple profiles, informing about the user’s unique visits to the site. Push notifications will only be sent to one profile, which will reduce the deliverability of messages. In case of inactivity of other profiles, Cloud Manager automatically removes the user from the subscriber list.
When a mobile device or computer receives a weak signal or there is no Internet connection, the user will not receive push notifications. Messages will only be sent when the service is back.
The push notification management system requires not only an Internet connection, good service coverage, and disabled power saving mode. The user will not receive messages even if airplane mode is enabled. Restoring the device settings will resolve this issue.
Push notifications will be delivered even if the subscriber closes the website. However, for the messages to be displayed to the user, the browser must still be running in the background.
In line with the point mentioned above, the browser must be running in the background so that the subscriber receives push notifications. However, for some devices, the browser can be active and work “in the foreground”.
Usually, push notifications are delivered despite the AdBlock plugin enabled. However, it can happen that ad blockers and corporate firewalls block the URLs of push notification providers.
Cookies are text files saved by a browser in order to store and remember information to identify users. If they clear cookies, they will not receive any web push notifications.
On mobile devices, push notifications appear when a notification bar is expanded. There are limits depending on the device, so some messages can be automatically removed.
Push notifications are only provided when the mobile device is turned on. If the phone is locked for a long time, messages sent during this period may not be delivered or the user will miss them.
The Service Workers application gives you the ability to control the retrieval of available resources from your domain. This is crucial for push notifications. If the service-workers.js file is uninstalled, notifications will not be delivered to recipients.
Sometimes a browser may not have permission to download data. In this case, the user will not receive a push notification. If the screen is locked, the user may see the notification title and the information about the private message.
When configuring push notifications, a specific message expiration time can be set. If the user is not connected to the Internet for a long time, the notification sent during this period may not reach the recipient or will be skipped by them.