Fix For Firefox 3’s ‘Open in Tabs’ Overwrite Bug

Firefox3bug_thumb5On May 25, 2008, I wrote this post about Firefox 3’s ‘Open in Tabs’ Overwrite Bug. That post has been, by far, the single most accessed post on The Daleisphere.

I’m delighted to report that thanks to Martijn Warger (see comment 57 here), there is now a tiny Firefox extension that completely solves the problem.

The Problem

For as long as I’ve been using Firefox (a couple years now), middle clicking on any group of tabs in a folder would open all the tabs in the group while simultaneously overwriting all currently open tabs – a very valuable function when you routinely browse by folders as I do.

This was the case when when the about:config


option was set to true – its default setting.

From the early Firefox 3 betas up through to the current Firefox 3.0.1 version, this has been broken. No matter how that option was set, opening new tab groups appended the new tabs to open tabs instead of overwriting them (more details in my original post).

The Solution

[June 30,009 Update: Martijn has updated the ReplaceTabs Extension to work with Firefox 3.5. Read about it on the Bugzilla here or download it here. I have tested it both on the iMac and on Windows 7 RC and it works just fine. Do not used the old one crossed-out below if you have Firefox 3.5 or above]

Click here to download/install Martijn’s "ReplaceTabs Extension 1". You will need to open the.xpi file with Firefox to install the extension. after installation, Firefox will need to be restarted for the solution to take affect. Once restarted, make sure the about:config option (see picture below) is set as follows:

browser.tabs.loadFolderAndReplace = true

For those new to "about:config", type "about:config" into the Firefox navigation bar (see picture) and press enter. That will bring up Firefox’s about:config screen (the place to futz with Firefox’s advanced settings). Scroll down to the ‘browser.tabs.loadFolderAndReplace’ option and make sure its ‘Value’ is set to ‘true’ as pictured below. If it is set to ‘false’, double left click it to turn it to true. That’s all that’s to it.

Fix For Firefox 3's 'Open in Tabs' Overwrite Bug

From then on, middle clicking on a tab group will open those tabs and overwrite the currently open tabs just as Firefox has done for years. Thanks so much Martijn!



14 Replies to “Fix For Firefox 3’s ‘Open in Tabs’ Overwrite Bug”

  1. Hi Dale,

    I’m glad you like that tiny extension of mine.
    I wrote it because my brother was also really bothered by this change of behavior and I couldn’t find an extension that would revert it.

    Note that I already set the browser.tabs.loadFolderAndReplace pref to true in my extension, so you should not have to do that any more, after you’ve installed the extension.
    I also added an option to change it, under Tools->Options->Tabs.

  2. Thanks Martijn. Any word on getting it on the official Firefox Extensions page. Not only will it be easier for folks to find, it will make people feel a little safer about adding it in if its there.


  3. Big thanks Martijn. This single item has made me not install Firefox 3 on several computers. Thanks for fixing what the developer’s broke.

  4. thanks! broke down and allowed the psuedo-forced “update” to FF3 yesterday, and this change in functionality was immediately noticed. quick search revealed the problem and your fix. works as expected. tak & lycka till!

  5. Ok, now the extension was reviewed or something:
    “Your nominated add-on, Replacetabs Extension, has been reviewed by a Mozilla Add-ons editor who decided to retain your add-on in the sandbox.
    Comments: One of the requirements to go public on is that your add-on must have some reviews either on AMO or elsewhere on the web. See for some ideas on how to do that. If you have non-AMO hosted reviews (e.g. on blogs, forums, etc… please send those links in). Once you have those reviews in place, please renominate to go public on AMO.


    If you have questions about this review, please e-mail or join #addons on

    So I guess I need reviews or something on AMO to get the extension out of the sandbox, so it can go public (but which I would have to renominate it for. Man, this is complicated!)

  6. Apparently, they broke the new functionality, as well. I was one of the people who explicitly set the behavior so that “Open All in Tabs” would open all of the bookmarks in new tabs. With FF 3, the problem is that it overwrites the tab I currently have open! I liked being able to open a whole folder of tabs, but now I have to get into the new habit of creating a new tab first.

    I guess it’s time to learn how to write extensions so I can get the old behavior back. I really wish developers wouldn’t change existing behaviors like this without providing ways to keep the old behavior.

  7. Martijn, sorry I just noticed your comment from August 27 in my moderation queue today (Sept 15). My blog has anti-spam countermeasures which held your post up.

    You can certainly refer the Mozilla editors to this page as one external review! I love your add-on. I’m using it on four computers now – two XP PCs, one Vista 64 and one iMac! All working great.


  8. While I enjoyed the default FF2 behavior, I can see merit in the argument to change the default. I wouldn’t cry about having to change a single cvar to make my experience suitable.

    That said, why BREAK/REMOVE the functionality? The logic escapes me.

    Also, it appears that the download link is bandwidth exceeded! I hope I saved the copy from my home machine!

  9. *sigh* This feature is broken yet again. Firefox 3.5.7 shows the ReplaceTabs Extension as “not compatible” with Firefox.

    I can't decide which is more aggravating… that somehow Mozilla keeps continually finding ways to break the fix posted here, or that they seem oblivious to the fact that this feature really did exist at one time in their browser, and should be fixed by THEM.

  10. Unfortunately ReplaceTabs Extension 1.1 does not work in Firefox 3.6. I had to revert back to 3.5 pending an update by Martijn. I don’t know of any other extension that solves the problem. I don’t have a direct way of contacting Martijn. I left a requst for an update on Bugzilla here:nn I also added to the chorus of requests for an update on the official Mozilla add-ons page here:nn, if you are out there, please help us out. Also, I suggested you add the donatoin button to the downloads page. I’d certainly be happy to kick in a $5 or so PayPal donation every time an update is needed. nn…Dale

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