A new bookmarks section with a mirror option have been added. That option
has never been released yet.
This new options is limited since it affect all paths without distinction. In
case where a repository is interacting with multiple peers, being able to
control behavior on a path basis can be quite valuable.
In addition, having more variant of behavior would be interesting, especially a
mode where no bookmark exchanged is tried at all. Such new mode (implemented
later) make a lot of sense for configuration on a path-basis.
Configuration of the default behavior is still possible through the usage of
generic path configuration. The "old" config, becomes:
Nit: KNOWN instead of KNOW, and pluralize MODES. I'd also be fine with VALID or SUPPORTED instead of KNOWN.