209 reviews for this add-on
  • Due to the fact that Google now uses page-load speeds as a ranking factor; this is a critical plug-in that any SEO web-master needs to have installed in their browser. It gives high quality information that cant be overlooked.
  • Please make this addon comaptible with Minefield beta11 pre.
  • Really nice plugin to improve website performance
  • http://ptclike.blogspot.com/
  • Unstable and buggy!
  • YSlow is a usefull add-on especially for bigger sites. Used in combination with Googles Page Speed, webmasters have two very powerfull tools for analyzing websites. Even google suggests to use YSlow for web page analysis.
  • Wow, I really needed this! I love it!
  • We integrated YSlow into our release cycle. QA opens a show stopper bug, each time our grade goes down...
  • =)
  • woops forgot to download firebug.
  • buggy and very confusing, what is smush it ? isn't it supposed to compress images.
  • I got empty page with source when clicked on 'Server' link in YSlow under Firefox 3.6:

    It is impossible to jump bakc.
  • YSlow 2.0.5 rendered FF3.6 (Vista, 32-bit) unusable - after more than 10 crashes, I disabled it. It looks like the YSlow 2.0.6 update today fixed the problem.
  • There were about 5-6 updates (1 per day) that all kept breaking and failing to fix the previous bug. Don't Yahoo test these things? 2.05 wouldn't even install!! Today's 2nd update seems to work so far. Fingers crossed.

    Annoyed at all the errors and poor QA, but it is still a nice plugin when it works.
  • This is a great product with excellent utility. Good turn around on fixing the crashing error.

    I look forward to more quality updates in the future.
  • Thanks for the fix, everything's working now.
  • It used to be a good addon, but recent updates show that testing is no longer done before releasing a new version. Now each update is worse than the one before. :(
  • Running:

    OS X 10.5.8
    FF 3.6
    YSlow 2.0.6

    FF would not open at all. Had to manually remove the extension (Library/Application Support/Firefox/Profiles/[].default/extensions/).
  • Crash Crash Crash!!! In Firefox 3.5.7!
  • it makes FF crash a lot of times, i would never recomend to install it or install it at all
  • Firefox could not install the file at

    https://addons.mozilla.org2.04 won't install under FF 3.6:
    because: Not a valid install package
  • YSlow 2.0.5 crashes Firefox 3.5. YSlow 2.0.4 causes problems with extension DownloadThemAll, and maybe other extensions too.


    I've switched to the open source Google Page Speed:
  • When can we expect a version compatible with Firefox 3.6?
  • Can break some web sites that use AJAX, so not an option for me (unfortunately).
  • I found a small bug: when I install this add-on on OSX the bottom of Firefox Preferences window is cut off, so some of the controls aren't accessible.

    Anyway that's a really great utility!!!