The Live Bookmarks updates feature of Firefox will check for new RSS update at each hour, but if you feel that the time interval is to great, you can modify it!
- Open Firefox:
- In the address bar, type the about: config and press Enter.
- Click I'll be careful, I promise!.
- Right click on any of the entries and select New > Integer value.
- Click on the OK button and specify the number of seconds between each update - the minimum allowed is 60 seconds .
E.g with a 360 seconds delay:
- browser.bookmarks.livemark_refresh_seconds >user set> int> 360
- Restart Firefox, to validate the changes and as from now your RSS feeds should be updated more often.