Firebase allows you to track and monitor different aspects of your app using its Analytics tool.
If you want to be able to track the URL of the posts that have been opened in the app you will need to set up a custom dimension in your Firebase or Analytics account.
The objective is to tell Firebase to track a specific parameter (the URL) of a post view event.
Unfortunately, this needs to be done manually, as Firebase will no longer track all parameters tied to events, they have also applied a limit of 50 parameters tracked on free Firebase accounts. In the past, they used to track all parameters on all events (A LOT of data!), which was certainly a problem on their end since most Firebase accounts are free.
The first step to set this up is to access your Firebase account (https://console.firebase.google.com) and click on "Custom Definitions":
Now go to "Create custom dimensions":
Fill out the form using the following values and click "Save":
Now that you have a custom dimension created Firebase will start tracking the "url" parameter of your "post" event, it might take up to 24 hours until the tracked data is available for you to see in your Analytics account.
Once enough data has been tracked, follow the instructions below to see the list of post URLs:
Go to "Events" and select "post":
Scroll to the bottom of the screen and you will find the statistics for the custom dimension you created: