While other flatpak apps have no problems. Any suggestions?
The lag would be noticeable when you launch Firefox with stopped container (for example after reboot or manual stop).
Ok, I’ve tested this, I’ve noticed a lag of a couple of seconds for the first time I launched a distroboxed app.
Sounds about in line with what I’d expect. If that works for you where the flatpak doesn’t, then it at least makes a viable solution for the short term (though I don’t know how much overhead would be introduced). A minute of delay is ridiculously long for startup, so I still don’t know why you were having that issue with the flatpak