Created attachment 236178 [details]
Proposed patch

Changelog (copy/pasted from upstream):

    * New `digest-type` configuration adds optional more widely supported `multipart/mixed` format
    * New argument `--only-new` on the `add` command to ignore entries in feed
      when added, so only new entries will be sent.
    * Fix exception when parsing a feed with a linebreak in its title
    * Add a new `subject-format` setting, customise the subject line
    * Removed '$' interpolation in config file to allow URLs containing dollar signs. Interpolation was not fully supported, and the placeholder would not survive a second save. Config files with ${...} placeholders will need to be manually edited after upgrading, or a save forced by adding and removing a fake feed before upgrading.
    * Fix default HTTP User-Agent to use `rss2email` instead of `feedparser`, and fix `user-agent` setting to consistently apply to both outgoing emails and HTTP requests. This introduces a couple of potentially breaking changes:
       o Configurations that came to rely on the `feedparser` UA string should adjust to the updated UA string going forward.
       o Configurations that came to rely on the unintended behaviour, that configuring the User-Agent header in emails does not affect HTTP requests, should use a custom `post-process` hook instead.