Does anyone know whether it is possible to insert an image (for example a banner image) above the heading on discussion pages to alert learners to the fact it's a discussion in a more visual way?
Good morning, @ELLPIP ...
I do not believe this is possible. However, you might try the solution that is outlined in this other topic: Solved: Add icon into text header - Canvas Community. There are many icons to choose from, so hopefully you'll be able to find something that fits your needs.
I hope this will help a bit. Let Community members know if you have any other questions about this...thanks!