By default drone uses a session file. It is by default created in $HOME and it is not always useful. You can override it by a system property but if you don’t want such a file and can’t wait for the fix (should be in Drone 2) then you can write a small Arquillian extension to skip it:
TomEE embedded made several progresses recently and it is nice to use with Arquillian. Since it is fully integrated with Arquillian you can deploy 2, 3 or much more webapps in the TomEE embedded instance…but then you have an issue: CDI. CDI extension mecanism is based on Java ServiceLoader mecanism. It means it uses META-INF/services/* to load its extensions. The issue: TomEE embedded is embedded. Of course it shares its container classloader with all applications but in this case you’ll get in 90% of cases your extension as well (cause of Maven, gradle, …). So it means if you deploy your application with the desired CDI extension and another (a test one) where you don’t want them you’ll get trouble since the extension will be loaded.
How to avoid it?