Connecting to debugger doesn't always connect when application has already started

[eirvandelden]

What I did

• In a Rails 6 application
• add require "debug/open_nonstop" to config/development.rb
• Place a breakpoint
• Start the server (I use puma-dev to automagically start my app)
• Go to the url that will trigger my breakpoint
• Go to Nova and start the Ruby Remote Debug task

What I expected

• Debugger to connect, displaying continue/next/step into options

What I got

# server output
app-cb1cd720[41292]: DEBUGGER: Connected.

# Nova Debugger output
[Multiple lines of the following]
Request “stackTrace” failed: requestFailed(Optional("Failed"), nil)

• Debugger task is running
• buttons for continue/next etc, but they are not functional

Fun fact 1: If I follow the same steps using VSCode and the vscode-rdbg extensions, it does work
Fun fact 2: If I set a breakpoint by clicking in the gutter, the breakpoint gets deleted and execution doesn't stop. EXCEPT when I also connect VSCode, then VSCode will show the correct line when hitting the breakpoint.