So, yesterday I installed CalyxOS(6.8.21) on my Fairphone 5. It worked like a charm! But unfortunately I wasn't able to install a lot of basic apps via the Aurora Store (4.7.0) like, Firefox, Brave, OsmAnd, etc. Nearly every App I tried to download, I got the error message that the application is not available for my Device.

Here is what I did to fix my Problem. Maybe it will help some others.
- I deleted Aurora Store and installed it again via F-Droid store.
- I deleted F-Droid Store and downloaded the newest APK. Repeated Step 1.
But what finally worked was to change the device in Auroras Spoof Manager.
Go to Settings > Spoof Manager > Change to Samsung Galaxy S24 Ultra.
I don't know if there are any downsides If you change to an other device than what you really have, or If other devices work too, but for my part I didn't encountered any errors. Every app works fine.