By James Edwards

Dust-Me Selectors Version 2.0

By James Edwards

After many months of toiling in our secret underground laboratories, Dust-Me Selectors Version 2.0 is finally here!

If you’re one of the many people who made suggestions or commented on the original version, you’ll be pleased to know that the new version incorporates everything you asked for and more.

It was quite a challenge to bring all this together, particularly since Mozilla’s documentation is so … er … erratic (in fact for some functionality I had to look in Firefox’s source code just to figure out how it’s done!) But there’s nothing like a challenge to exercise the mind, and I think you’ll agree that the final result is well worth the gritty struggle.

To summarise the new features:

  • New spidering capability — it can spider either a Sitemap XML file, or an HTML sitemap (ie. it will spider one link deep from any page).
  • Shows which selectors have been used, as well as unused.
  • Data storage has been taken out of the preferences system and into the filesystem — data is stored in JSON files in a user-selectable
  • Better support for Conditional Comments — it can now recognise any number of stylesheets within a single comment.
  • Extended automation so it can re-parse a page automatically whenever the DOM changes programatically.
  • Comprehensive user preferences.
  • Support for Flock.
  • A spiffy new icon, courtesy of Alex Walker

For more information, documentation and to install the new version, check out Dust-Me Selectors on

  • Victor

    And now the big question…Does it support Firefox 3? :)

  • No – I’m gonna wait til it’s out of beta; mozilla have an annoying habit of making massive changes at the last minute.

  • Rick

    The Firefox addons update feature doesn’t find the new version.
    You have to (remove 1.1 first?) add it manually.

    (tools>addons “find updates”)

  • Chris

    Fails to work under Linux (FC6) Firefox

  • Christoph Roeder

    For me it’s not working, too. (Kubuntu Gutsy with FF

    “Not working” means:
    – I can’t view the result
    – some popups stay open when clicking ok or cancel

    So for me it’s unusable :(

  • AlexxDesign

    Great tool, saves me hours of work ..

  • internet4u

    For me it is working, too. (Kubuntu Gutsy with FF

    It is a matter of file permissions

    After having set preferences, use the following folder:
    ! create a folder eg: dust-me in your home folder !

    it works like expected

  • Michael M.


    Great tool, but it didn’t quite do what I had in mind.

    I’m merging/copying/moving/cleaning a whole bunch of style sheets, and I need a way to find all the cases on a page where the code calls for a class=”fubar”, but fubar is not efined in the current style sheet.

    I realize that CSS is intended to not fail because a style is not defined, but it’s a pain to cross reference.

    Any suggestions? or hope for a mod to Duster?


  • Matthew

    I found this extension didn’t work at all as I navigated my site. It only seemed to be able to capture everything on a single page.

    I write Firefox extensions as well and decided to look through the code.

    To get the extension to aggregate unused items properly, I had to comment out this line in dustmeselectors.js:
    if(typeof used[current_key][current_index] != 'undefined')
    //delete used[current_key][current_index];

    It seems that it was deleting the key from the used tab without readding it. So redundancy meant kill both of them.

    Anyway, with that change it worked great for my site. Thanks much.

  • Matthew

    Trying it this way to see if the code paste works better. The comment is for the delete line around line 277:

    if(typeof used[current_key][current_index] != 'undefined')
    							//delete used[current_key][current_index];
  • Thanks for the info on these various issues – I shall investigate.

  • Bogeyman

    Simply Superb

  • Tom

    Hi James, I would LOVE to test your plugin, but is offline :/?

  • Hi James, I would LOVE to test your plugin, but is offline :/?

    Weird, Tom. We’ll look into that first thing tomorrow (AU time).

  • Thanks for the heads-up, that was a permissions problem that’s fixed now.

  • Jan

    I cannot install Dust-Me Selectors – I only get an error message from the add-on installer (-207) that it is not a valid installation file. I’m using Firefox under MacOS 10.4.11

  • dmkash

    I can’t wait for a version that works with Firefox 3! Will there be an announcement when this is updated? Thanks!

  • …This plugin needs some work.

  • Marco Luthe

    Unfortunately, it’s not working with my WordPress blog…

    Tried the spider function. I have a sitemap which is generated with the Google Sitemap Generator plugin by Arne Brachhold. Pointing to that file ( did not work and took ages without anything happening.

    Then I just tried “”… but as I was still logged into my WP account, dust-me tried to analyze even the WP admin folder.

    So I logged out and tried the root directory again… seemed to work, I mean it finished… well, I’ll have to take a good look at the results now if they are any good.

    I’m sorry, but I have to share Wolf_22’s opinion:
    It still needs some work… sorry.

    But a great idea, nonetheless!

  • Marco Luthe

    Root directory wouldn’t work either… only a few posts / pages have been spidered… what a pity.

    OK, as I can’t subscribe to comments here, can anyone upfate me via if anything important happens? As I said: I love the idea of this plugin.

  • Dimitri

    Fantastic tool! Works like a dream.
    I’d love it more if it could delete unused selectors for sites I’m designing and want to clean up the css – either through a preview of files on my computer (before uploading) or through ftp access (especially for php or asp sites)

  • Alex Y

    strange but it doesn’t eat mine google-generated xml sitemap..
    It’d be helpfull if you provide xml sample some place here.

    PS HTML with links works fine.

  • xfinx

    I noticed that the tool can not handle url’s which do not begin with http:// but with //
    All browsers support the //

    Cheers and thanks for the great tool!

  • inSay

    I love this tool, but I can’t declare function Block(){}, because you used it in the global namespace. Please, use own namespace for this objects.

  • Elpie

    This extension is the only thing preventing me from using Firefox 3. I find it invaluable for site design and just had to add my voice to the calls for an upgrade :)

  • EoN604

    Hi guys,

    Only just learned about this Dust-Me Selectors today from a friend who recommended it. Sounds like a fantastic idea, but doesn’t work in FF3! Any chance you could mod this to work? As I understand, it’s usually a very easy process to make a FF2 extension compatible for FF3. I look forward to using it!


  • dont

    I use this all the time.. its killin me not being able to use it with FF 3.0. Im about to create a portable FF2 just to accommodate.

    I have subscribed to the RSS feed and will keep an eye on the download page

  • There’s a new version out today with FF3 support :)

    Please report any continuing issues to that blog post —

  • Bob

    It’s keep crashing on portable firefox 3 :(

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