The “field blacklist” is a list of fields that are to be treated specially in R4J. In particular:
Changing an issue's blacklisted field doesn’t trigger a new revision of the issue.
Blacklisted fields are not included in any revisions of the issue that are created while they are blacklisted. However, the fields are included in any revisions of the issue created while they are not blacklisted.)
Blacklisted fields are not displayed in the R4J details view. (Note that the Summary and Description fields are always displayed, even if they are added to the blacklist, since they are integral to requirements definition.)
Fields that have been added to the blacklist can be removed from the list, at which point they are no longer treated in the above ways. For example, changing an issue’s field that was blacklisted for some time again triggers a new revision of the issue.