Capturing Android traces is tricky, because the main mechanism is effectively to watch the device logs and filter for your application.
OpenFL has I think a 'openfl trace project.xml android' that will launch and filter the traces in the terminal.
The problem with FlashDevelop integration is that this log monitoring doesn't stop when your application is closed/killed so FD doesn't know by itself how to stop this monitoring process.
An alternative approach, integrated in FD and cross-targets, would be to use the FlashConnect logger. The connector class is in FD program files under Library/classes/HAXE. It is even possible automatically route Haxe traces through it. However I didn't try so that will require some investigation to make it work, but basically it creates a socket to send traces directly to FD exe.
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