It looks like if a class is set up to always trigger an interaction (as in interaction applies to class) and that class is later added to an object which already has classes, it will not show in the navigator as having an interaction attached (no green lightning symbol) making it impossible to later find the interactive element. Looks like oversight to me.
Thanks for posting about this class based interaction issue.
I was able to reproduce this issue on my end and have reported this to the team.
We’ll look into this more and I’ll post back here when I have more information for you.
Thank you for looking into it. Since IX2 were advertised as having a great re-usability (and latest fixes ensured that) I thought my use case was a mundane one and was surprised to see this little bug.