Thanks Scott.
So, this text in the description of .xset.retention.<retention
id>.duration is defective, right? Arch 9.2.1:
"This value shall be specified as a positive number of milliseconds,
or as “forever,” which is represented by a value of -1."
Perhaps this should be replaced by:
"This value shall be specified as a non-negative number of
milliseconds, or as “forever,” which is represented by a value of -1."
- Mike