Bitwig runs each plugin in a separate process, so you need to attach the debugger to the plugin host process rather than to bitwig master process. You can do this easily after the plugin has been loaded.
What worked for me was to start the host from the command line in Terminal: the DBGs at that point were being printed in that Terminal window, while still retaining the possibility to attach the debugger
you want to make a change to the code, so you select the track your plugin is on in bitwig and hit alt+a to unload all plugins from that track. this also automatically stops the debugger in visual studio.
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