I find that generally if Safari is set to get rss feeds they stop refreshing and you have to quit and relaunch to get real refreshing. This has happened for a long time but happens with the most recent build too (r69429 right now.) Just thought I'd post it and see if anything can be done.
This is not a WebKit bug. WebKit does not handle RSS feed refreshing in Safari. Please file a Safari bug at https://bugreport.apple.com/
Correct. Marking as INVALID as an issue outside open source WebKit per our policy.