* Added release notes for secrets.yml and mentioned it in the highlights
* Added release notes for Mailer previews and mentioned it in the highlights
* Added release notes for Module#concerning
* Removed mention for AV extraction from the highlights
* Rearranged the major features to put highlighted features first
* Various improvements and typo fixes
[ci skip]
The previous implementation of BacktraceSilencer#noise did not
work correctly if more than one silencer was configured --
specifically, it would only return noise which was matched by all
silencers.
The new implementation is such that anything that has been matched by
silencers is removed from the backtrace using Array#- (array
difference), ie. we now return all elements within a backtrace that
have been matched by any silencer (and are thus removed by #silence).
Fixes#11030.
