CLion Remote Debugging In Docker Container Not Working - Breakpoints Not Hit

When I use CLion try to debug my test application in a container running on a remote server - in this case it's an Ubuntu container on a RaspberryPi - the break point I set in the main method is never hit and the application just hangs.

There is no error show in CLion and it too just waits indefinitely. If I list the processes running on the remote container I see the application listed in a a Running/Runnable state. If I try to execute the application as a release then it works normally.

I've also tried remote debugging directly on the RaspberryPi itself i.e. not in a container and it works as expected i.e. break points are hit.

I couldn't see anything in the CLion docs, do I need to expose another port of the container or is there something else I am forgetting to do?

Update

Interestingly, I tried clicking the 'pause' control in CLion and then 'continue' and then the first breakpoint is hit in the main method. I don't have an explanation as to why this works but its annoying to have to do this each time I'd want to debu