Feedly is easily your favourite RSS reader (and ours), but that doesn't mean it can't stand to get a few improvements. For those who like to tweak, here are extensions and user scripts that make Feedly even more useful.
Open Tabs in the Background
By default, Feedly opens all links you click on in a new tab. That's great, except for the fact that it also steals focus from the tab you're on. If you're the type to load up a bunch of tabs at once, Feedly Background Tab for Chrome is an extension that does just that. Hit ";" when you're on an article and it'll open up in a background tab. Firefox users can get the same thing with this userscript.
Give Feedly a Google Reader Look
Not a fan of Feedly's look? If you're pining for the good old days of Google Reader, GGReader for Chrome brings back the Google Reader look. Likewise, Firefox users can install this script to accomplish the same task (without the goofy logo of GGReader). You might also want to check out Feedly Wide and Clean for Stylish.
Instantly Subscribe to RSS Feeds
Sometimes when you come across a new site that you love you just want to quickly find and subscribe to its RSS feed. Unfortunately, that's not possible with just the Feedly web app. To make things easier on yourself, Add to Feedly for Chrome adds a button to easily subscribe. Firefox users can use RSS Handler for Feedler to add Feedly to the subscribe button.
Make Feedly More Minimal and Easier to Read
Feedly is already pretty minimal as far as its interface is concerned, but if you really want to strip away all the cruft, Feedly Readable is a Chrome extension that strips away Feedly's interface when you're reading longer articles.
Add an Unread Counter to the Feedly Tab
One thing that Google Reader always did that Feedly doesn't is update the unread count on the tab. It's a minor inconvenience, but if you're like me and keep Feedly open in the background the counter serves as a nice reminder to check back in on RSS feeds every now and again. You can get a small unread badge back with this user script or this Chrome extension if you prefer a button. Once it's installed, Feedly will automatically scrub for new items in your feed and show you an unread count.
Bonus Tip: Add Even More Functionality with IFTTT
It's no secret we're fans of the automation service, If This Then That, and it has fantastic integration with Feedly. With it, you can easily save articles to Pocket, Evernote, or Instapaper. If the above extensions and user scripts aren't adding what you're looking for to Feedly, IFTTT is a good place to start.