Thread still showing as running after termination

[Gama11]

When running the following code (thanks for the code example @gepatto) and pressing Space to open a file dialog, a second thread appears in the callstack view:

package;

import lime.ui.FileDialogType;
import lime.ui.FileDialog;
import openfl.events.Event;
import openfl.net.URLRequest;
import openfl.display.Loader;
import openfl.display.Sprite;
import openfl.ui.Keyboard;
import openfl.events.KeyboardEvent;

class Main extends Sprite {
    var dialogOpen:Bool = false;
    var l:Loader;

    public function new() {
        super();
        stage.addEventListener(KeyboardEvent.KEY_DOWN, stage_keydown);
    }

    function loadComplete(e:Event) {}

    function stage_keydown(e:KeyboardEvent) {
        switch (e.keyCode) {
            case Keyboard.SPACE:
                selectImage();
            case Keyboard.DELETE:
                if (l != null) {
                    l.unload();
                    removeChild(l);
                    l = null;
                }
        }
    };

    function selectImage() {
        #if !js
        if (dialogOpen)
            return; // prevent multiple dialogs
        if (l == null) {
            l = new Loader();
            l.contentLoaderInfo.addEventListener(Event.COMPLETE, loadComplete);
            addChild(l);
        } else {
            l.unload();
        }
        var dOpen = new FileDialog();
        dOpen.onSelect.add(function(path:String) {
            l.load(new URLRequest(path));
            dialogOpen = false;
        });
        dialogOpen = true;
        dOpen.browse(FileDialogType.OPEN);
        #end
    }
}

When the file dialog is closed, the thread should terminate, but the UI doesn't seem to update. I added some traces and found the following order of events:

threadStart {
    threadId : 0
}
threadStart {
    threadId : 2
}
threadExit {
    threadId : -1
}

So it looks like we don't get a valid thread ID on exit. Possibly a bug in hcxpp (@nulld)?

[Gama11]

HXCPP issue at https://github.com/HaxeFoundation/hxcpp/issues/845.

[nulld]

Looks like we receive THREAD_TERMINATED event from cpp.vm.Debugger with threadNumber :-1. So it's a bug or undocumented behaviour: https://api.haxe.org/cpp/vm/Debugger.html#setEventNotificationHandler