CSP violations introduced by Addons / Extensions

We've noticed that Extensions and Addons are responsible for CSP reports,
and it's hard for us to debug that.

It would be nice if there was a flag in the report that specifies if the
violation was initiated by an extension or an addon.

I understand there are challenges on doing this (eg, an extension can
inject a script which later generates a report).

Being able to differentiate this problems would assist us to more quickly
and efficiently reproduce and triage bugs.

This goes hand in hand with the other request (generating a DOM event/error
on CSP violations).