I’ve just released an update to the Feed Sidebar Firefox extension that adds essentially every major feature request that I’ve gotten since version 1.2 came out:

• Biggest improvement: Feed Sidebar now has its own history for tracking which items are read, rather than using the browser history. This means that you can clear your browsing history without clearing your feed reading history.
• Feed Sidebar now uses Firefox’s native feed parser. This slims down the code in the extension and (probably) the number of bugs.
• The sidebar now remembers which feeds you collapse, and the next time those feeds load, they’ll still be collapsed. This has been requested ever since the first version came out, so I feel good about getting it done.
• You can unsubscribe from a feed directly from the sidebar by right-clicking on it and choosing “Unsubscribe.”
• You can choose to display all items from all feeds, not just new items. If you enable this (in the Feed Sidebar preferences dialog), items you’ve read will be light gray; new items will appear as they always have.
• I moved the update status (“Next update: 11:00 PM”, “Checking 123 of 456 feeds…”) to a status bar inside the sidebar. This clears up room in the toolbar for more buttons, if necessary.
• The first time you run Firefox after installing the extension, the sidebar will open automatically, and the Feeds button will be added to the toolbar. (I had gotten lots of comments along the lines of “I installed it; now what do I do?” Hopefully, this will mitigate that problem.)

Overall, I thinks this version is much sleeker and much more usable than the last, which is pretty much all that matters. You can download the latest version of Feed Sidebar from Mozilla Add-ons.