I use this addon called Tab Mix Plus a lot (it makes the tab bar multi-row), and one of its extra features is tab duplication. In fact, there's a whole ton of things it lets you add to the right-click menu:

http://tmp.garyr.net/help/#Menu_-_Tab_Context_Menu

I will warn you that TMP is a complicated addon with a lot of settings. If you're easily overwhelmed by large options menus, you probably won't like it.

If you don't feel like getting an addon, you can do what I do to dupe the current tab and just hold Ctrl while hitting Refresh.

But there is something unique about this "duplicate" option in chrome that when you duplicate, it not just creates a new tab with the same web-address, but it also copies the typed content that you wrote in the tab you wanted to duplicate.

For example, let us say i wanted to complete typing this reply on another tab, all I had to do is duplicate, and continue from where I left off on the original tab without starting all over again or without copying and pasting.

So it also duplicates all the content both typed or changed of the tab you choose.

In Firefox, you can duplicate a tab with its history, by

• holding the Ctrl key while dragging the tab with the left-click key along the Tab Bar
• You will see a small arrow between tabs as you pass the boundary between the tabs
• When positioned as you wish, release the left-click key and the duplicate of the dragged tab will be inserted.

Tab Mix Plus is a good extension, but is complicated with a lot of settings. Other lighter-weight extensions with a "duplicate tab" feature are:

• Tabberwocky: https://addons.mozilla.org/en-US/firefox/addon/tabberwocky/
  • Note: As of this posting, not yet compatible with Firefox 4
• Tab Utilities: https://addons.mozilla.org/en-US/firefox/addon/tab-utilities/
  • Compatible with Firefox 4
• Tab Utilities Lite: https://addons.mozilla.org/en-US/firefox/addon/tab-utilities-lite/
  • Note: As of this posting, compatible only up to Firefox 4.0b8

You solved it, but I still would have loved to have the "duplicate" feature without having to use my keyboard.

You want it to duplicate content, as well?

Well, Firefox already keeps track of most user input on forms so that it's (somewhat) safe to use Back and Forward when typing. I can confirm that the Duplicate Tab feature of TMP successfully duplicates what you've typed so far in those cases.

However, in places that Firefox is unable to save text for - like the specially-coded text editor I'm using right now to post on this forum - it doesn't copy the text.

I'd be surprised if one of the other options available to you does copy this text, but if it does, all the more power to you.

In Firefox 4 you can duplicate a tab with a middle-click on the combined Reload Stop go button on the right end of the location bar.

@cor-el - I don't understand what you mean...

Firefox 4 no longer shows a Reload and Stop button on the Navigation Toolbar, but has a button on the right end of location that shows the different states. During the page load process it shows as a Stop button and after the loading has finished the button is changed to a Stop button. If you type in the location bar then that button becomes a Go button.
You can middle-click that button to duplicate the current tab to a new tab.

i have the same problem... the weird thing is that on the same sites it used to work in v3 it now stopped working in v4... in my case its in a forum and it only saves the content of the "subject box" and the "message body" box... all text boxes and drop-down-boxes inbetween stay empty when i duplicate the tab maybe some content saving setting or something changed? id really love to get this feature back

Tab Mix Plus and Toolbar Buttons 1.0

cor-el

AWESOME! IT WORKS! (clicking the Reload button to produce a Duplicate Tab) Worked perfectly in Firefox 7! Thank you SO MUCH for this. Would you believe that I kept Firefox 3.0.4 up until last week (Nov, 2011) because of Duplicate Tab? (I used it so frequently). But I was forced to update to Firefox 7 if I wanted to view/edit my Myspace profile. And the Firefox 7 alternative, about holding the ctr key while dragging the tab over was not for me. I kept opening up the Bookmarks menu if I didn't do it just right or my click wouldn't register and I'd have to do it again. And, it was a two hand operation. So I had to put my sandwich down to do it ;) Anyhow THANK YOU again for this simple alternative to the Duplicate tab add on. I'm hoping someone else will find this. I just stumbled upon this post and am so glad I did!