Some would say Tabs is one of the most useful features of a browser that uses tabs.

https://addons.mozilla.org/en-US/firefox/addon/tab-killer/

However the longtime extension author (that is trusted) has the version for 3.6.* on his homepage at http://piro.sakura.ne.jp/xul/_tabkiller.html.en#download as the Download Latest Version (via HTTPS, GitHub) link.

I downloaded the feature. When I tried to open it, Windows jumped in and said it could not open the file. Thanks anyway. Bill

Try clicking on the link instead and a prompt to Allow and then install should happen.

Or if you still have the .xpi downloaded then either drag and drop the .xpi onto a open Firefox window or in Firefox go to File->Open File (Ctrl+O) and browse to the.xpi and open to install it.

Windows does not have a clue of what to do with the .xpi file and can be confused with Firefox Theme .jar files in thinking it is Java related.

James, I used https://addons.mozilla.org/en-US/firefox/addon/tab-killer/ . It responded: Tab Killer 1.1.2007042541 could not be installed because it is not compatible with Firefox 3.6.18.

There is a version (2.0.2009110201) on the developer's homepage that is shown as compatible with Firefox 3.6.x

• Be aware that the developer has not updated the add-on to be compatible with Firefox 4 and Firefox 5; that is a sign that it may no longer be updated and may no longer work after you update from version 3.6.x of Firefox to Firefox 4 or 5.

Here is the developer's homepage; click on "Download", then click on "Download Latest Version (via HTTPS, GitHub)" to install.

• http://piro.sakura.ne.jp/xul/_tabkiller.html.en

wmaynard I gave you a link to where to get the version that works with 3.6.* in last part of my first post as I thought you were referring to that when you downloaded the extension instead of installing it in Firefox.

Not sure how active Piro is with his extensions now days compared to the earlier days.

@wmaynard

If you have that extension saved, drag the xpi into the Firefox window or use File > Open File... to install that extension into Firefox.

Windows may not know what to do with that xpi package, but Firefox sure as hell does.

Ed, look up a ways :P

Whoops, missed that!

https://addons.mozilla.org/en-US/firefox/addon/tab-killer/ . I still get this message for : Tab Killer 1.1.2007042541 could not be installed because it is not compatible with Firefox 3.6.18. Thanks anyway. Maybe there will be an update. I'm really surprised I can't turn it off under Tools > Options > Tabs.

Wait. I think I figured out what I was missing. I downloaded tabkiller.xpi and dragged it to Firefox. That seemed to work. Thanks everyone! Bill M.

What do you think of Tweaknow?

wmaynard here is the link again as you appear to be missing my first reply still. I am Not referring to the addons.mozilla.org page as that is a older version.

http://piro.sakura.ne.jp/xul/_tabkiller.html.en#download

Piro the extension author has the a more current version for 3.6.* on his hompage in the Download Latest Version (via HTTPS, GitHub) link.