In some cases, it’s possible to replace the default Pushover logo with a custom image which is shown next to the alert. However, in LibreNMS, I can’t find this option anywhere.
Any ideas?
That sounds like a setting in pushover itself?
It would need someone to add support.
The question still stands though. How do I show that custom image?
I would gladly develop something like that and contribute, but I have no idea if it’s a thing that Pushover or LibreNMS has to support.
I don’t know Pushover but if they expect you to send something to the api to do this then it’s in our code base.
The code for pushover support is in LibreNMS/Alert/Transport/Pushover.php
I think I found it on https://pushover.net/api/client
icon - The icon name of the application that sent the message. The image data can be fetched at https://api.pushover.net/icons/<icon name>.png. When an application changes its icon, this value will change.
Will see if I can contribute 
It was much more obvious than I figured. You can upload an image on Pushover’s website when navigating to your app. As long as you have the correct appkey set in LibreNMS, that should do the trick.