(In reply to Quim Gil from comment #12)
> (In reply to Andre Klapper from comment #9)
> > For my better understanding (and maybe others who might have the same
> > problem):
> > "Time to first action by Priority" - How is an "action" defined?
> 
> It means that someone (else, not the reporter) has changed priority,
> severity, etc. That the bug has some history of changes, although afaik a
> first comment is not counted (Santi must confirm). See Bug 13162, which tops
> the list, it hasn't seen any change since it was submitted in 2008.
> 
> (It belongs to the MultiBoilerplate extension which afaik is not part of the
> Key Wikimedia projects, a way to fine tune the list of products/components
> we scan is to remove those that show up in the top results.)
> 

Action means changes + comments done by someone, but not by the reporter. In this context, "Time to first action" means how long it took that someone (not the submitter or reporter) for the first time, made a change on any the bug's parameters or posted a first comment. 

This is the definition that Alvaro gime me but we can change it to "Time to first change", if you prefer.

> > Is "Time to
> > first comment" a subset, or disjunct?

"Time to first comment" is a subset of "Time to first action".

> > So: Could the framework query changes to the "Priority" value of one report
> > (via the "bugs_activity" database table in Bugzilla) and could one report be
> > broken into/represented in several lines, each line showing for how long the
> > report had that specific priority set?  I think this would make the lines
> > more meaningful. (Same might apply to Severity).
> 
> Following on Comment 7, this would be translated as
> 
> "How old are today the open bugs that haven't received any action yet,
> organized by their priority/severity today"? And last month (based on the
> priority/severity they had last month)? And a year ago (based on the
> priority/severity they had last year)?
> 
> As said, if Santi sees a quick way to fix this let's do it. Otherwise let's
> open an enhancement request for the next iteration.
>

Definitely. I can try something but I prefer to close the definition and meaning of the current charts before moving to new ones.