Inform the user when background content fetching finishes (but no retrieved content is new)
Currently Samizdat displays two messages to the user:
Some content seems blocked or unavailable. Attempting to retrieve it via Samizdat"
when a regular HTTPS
fetch()fails and plugins get deployed in the background
Newer version of this page is available; please reload to see it."
when all background plugins finish and there is content retrieved that is deemed "fresher" than what was found in cache
For completeness, we need a message displayed when background fetching is done but content is not deemed fresher.