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~/.local/share/Steam/steamapps/common/Neverwinter\ Nights/bin/linux-x86/tracy/Tracy
The binaries shipped with the game have a small patch applied to allow connecting after app start, which you can also find in ./bin/ if you'd like to rebuild them locally.
Configure
Enable tracy in For clients, you can find the toggle to enable this functionality in the Options UI (just search for "tracy" in the search box). Note that you will need to restart your game after changing this config.
For dedicated servers, you need to edit settings.tml:
[instrumentation]
[instrumentation.tracy]
enabled = true
port = 8086
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