.Multiple Tab Handler  (34KB) extension      
formerly: https://addons.mozilla.org/firefox/4838
now must be by name https://addons.mozilla.org/firefox/addon/multiple-tab-handler/ 
invoked from Tabs context menu for selected tabs
Sample Control cards for MTH creating text references to tab here in
 http://www.mvps.org/dmcritchie/firefox/multiple_tab_handler.txt

CopyURL Plus  (18KB) extension invoked from the main context menu
and/or the Tools menu can include a selection, since it only 
applies to the current tab.
Sample Control cards for CopyURLplus can be found within
 http://www.mvps.org/dmcritchie/firefox/code/prefs.txt

Both extensions are documentation in 
 http://www.mvps.org/dmcritchie/firefox/firefox.htm

 

The added features in Multiple Tab Handler (MTH) should be built-in to 
Firefox, which needs native ability to select and work with multiple tabs.

Multiple tabs are selected via Ctrl+click on a tab with this extension.
Specifically because you can select which tabs are to be included there
is no need for any option to allow or disallow inclusion of app-tabs.


Double Click Closes Tab :: Add-ons for Firefox
https://addons.mozilla.org/firefox/addon/double-click-closes-tab/
adds a feature that I think should be in Multiple Tab Handler, anyway
this extension is much more direct and smaller than other extensions
that can close tabs with a double-click and I go for less complicated
and smaller every time.


Summary of  Multiple Tab Handler, you may not pick up easily from
addons descriptions, comments, and extension's home page. 

The Copy URI  doesn't provide for a blank line after each title/url, 
easily fixed with with a customization option under copy make it the
default so you don't have to select options. (You could change about:config)
    Page Title , URL, spacing --
    %TITLE%%EOL%%URL%%EOL% 
For those doing HTML, keep the menu choices and besides above, add
    HTML links  multiple <LI> --
    <li><a href="%URL_HTMLIFIED%">%TITLE_HTMLIFIED%</a>
This will negate need for "Copy All Urls" extension for most people.  
From an individual page "CopyURL Plus" extension (from main context menu) is best and easily customized, is
better specifically because it can include text selection in the format.

But on the plus side,  it does not interfere with "Permanent Tabs Mod", nor does it interfere with my  tab style for stylish.
It has a very extensive list of options so many  it has tabs for 
options, so you can select or reject individual items. I choose 
default behavior for dragging tabs not the option of multiple 
selection by dragging.

Without MTH the default Firefox Tab Context Menu reads as
  New Tab
  Reload Tab
  Reload All Tabs        (grayed on single tab)
  Close Other Tabs       (grayed on single tab)
 _Open in a New Window   (grayed on single tab)
  Bookmark This Tab
 _Bookmark All Tabs...   (grayed on single tab) 
  Undo Close Tab         (grayed if none to undo)
  Close Tab
  

When one tab is selected  it adds the following to tab context menu (ordered and separators added via "Menu Editor" extension)
  Close All Tabs
  Close Right Tabs
  Close Left Tabs
  Save All Tabs
  Copy URIs of All Tabs
  Copy URI
  Close Other Similar Tabs {see options}
  Close Similar Tabs       {see options}
 _Duplicate Tab

When multiple tabs are selected, these are added to the tab context menu
  Reload Selected Tabs    - instead of Reload Tab
 _Bookmark Selected tabs to New Folder
  Duplicate Selected Tabs
 _Move to New Window
  Close Selected Tabs
 _Close Other Tabs
  Copy URIs of Selected Tabs
 _Save Selected Tabs as files

This extension Needs Customizing work (see my changes belows):   
Of course, nothing handles formatting better than "CopyURL Plus" for the 
active tab when selections are involved.  
The "Copy All Urls" extension works with all tabs but barely handles 
customizable format, and only one HTML choice.  Missing merge feature 
of "duplicate tab" extension.  The drag part of duplicate tab is now 
within Firefox itself, but is not the same as the "duplicate tab" 
extension.  This extension does extend the built-in duplicate tab 
feature to use with multiple selected tabs.

Needs a lot of work; 
-- Messed up personal chrome changes particularly with selected tabs, 
it reinstituted tab scrolling when not even needed, just because this 
extension was installed.

Use BACK button, or close-tab to return from whence you came, probably to
   http://www.mvps.org/dmcritchie/firefox/firefox.htm#multipletabhandler

======================================= MTH Options =======================================
General: change Move tab by dragging within from 400ms (delay) to 700ms.
  Action for dragging of tabs
   (x) Default (move and rearrange tabs)  [turned off] (x)    (_)Select tabs
     [x] Open popup menu automatically
     [x] Clear tab selection after the popup menu is closed
   (_) Swithch tabs dynamically
  Move tab by dragging within 500 msec  (default was 400)
   [x] Move selected tabs together
  Action for Ctrl(Command)-click of tabs
   (_) Close Tab (Firefox default)  (x) Toggle Selection of Tab
  Action for Shift-Click of tabs
   (_) Ignore (Firefox default)   (X) Select Tabs

Features:
  Save mode for tabs
   (_) Select from menu             (_) Exclude embedded resources
   (X) Include embedded resources   (_) Convert to Plain Text Files
  Detecting method for "similar tabs"
   (x) by Domain
   (_) by Host

Copy:  see detailed change below this section

Tab Selection Menu
   Thought I had everything checked off (default) but see I
   can scroll down and there are grayed out options for print/freeze/protect/lock tab.

Tab Context Menu  (everything is selected)

Advanced
  Order to close multiple tabs
   (_) Left (Top) to Right (Bottom)    (X) Right (Bottom) to Left(Top)
   [X] Close the current tab at last
  [X] Select tabs automatically, after they are duplicated
  [X] Select tabs automatically, after they are moved to another window.
======================================= New tokens ==========================
Version 0.6.2011082901 August 29, 2011 76.8 KB   New tokens  (WOW! -- except it doesn't work)
Improved: New place holders for meta info: %AUTHOR%, %AUTHOR_HTMLIFIED%, 
%DESCRIPTION%, %DESCRIPTION_HTMLIFIED%, %KEYWORDS%, and %KEYWORDS_HTMLIFIED%.


======================================= Examples of Pasted Links from Tabs ================
On the 'Copy' tab of MTH options, be sure to choose "Select from menu"

SIMPLE URL:                   %URL%
http://battellemedia.com/
http://blogs.nybooks.com/
http://jordychens.blogspot.com/

Page Title and URL:           %TITLE%%EOL%%URL%
John Battelle's Searchblog
http://battellemedia.com/
NYRblog - The New York Review of Books
http://blogs.nybooks.com/
Blogger: Blog not found
http://jordychens.blogspot.com/


Page Title, Description, and URL    %TITLE%%EOL%%DESCRIPTION%%EOL%%URL%%EOL%

: NYRblog | The New York Review of Books
: %DESCRIPTION% // %AUTHOR%
: http://www.nybooks.com/blogs/nyrblog/

: Tourism in Madeira islands Portugal
: %DESCRIPTION% // %AUTHOR%
: http://jordychens.blogspot.com/

: Firefox Customizations (Notes)
: %DESCRIPTION% // %AUTHOR%
: http://dmcritchie.mvps.org/firefox/firefox.htm#ext_table

: NYRblog | The New York Review of Books
: %DESCRIPTION% // %AUTHOR%
: http://www.nybooks.com/blogs/nyrblog/

: Tourism in Madeira islands Portugal
: %DESCRIPTION% // %AUTHOR%
: http://jordychens.blogspot.com/

: Firefox Customizations (Notes)
: %DESCRIPTION% // %AUTHOR%
: http://dmcritchie.mvps.org/firefox/firefox.htm#ext_table


HTML Link:                   %RT%<a href="%URL_HTMLIFIED%">%TITLE_HTMLIFIED%</a>                 
<a href="http://battellemedia.com/">John Battelle's Searchblog</a>
<a href="http://blogs.nybooks.com/">NYRblog - The New York Review of Books</a>
<a href="http://jordychens.blogspot.com/">Blogger: Blog not found</a>


HTML [Ref] Custom           [<a href="%URL_HTMLIFIED%" Title="%TITLE_HTMLIFIED%">Ref</a>]
[<a href="http://battellemedia.com/" Title="John Battelle's Searchblog">Ref</a>]
[<a href="http://blogs.nybooks.com/" Title="NYRblog - The New York Review of Books">Ref</a>]
[<a href="http://jordychens.blogspot.com/" Title="Blogger: Blog not found">Ref</a>]

WIKI ext <li> Link:             <LI><a href="%URL_HTMLIFIED%">%TITLE_HTMLIFIED%</a>
<LI><a href="http://battellemedia.com/">John Battelle's Searchblog</a>
<LI><a href="http://blogs.nybooks.com/">NYRblog - The New York Review of Books</a>
<LI><a href="http://jordychens.blogspot.com/">Blogger: Blog not found</a>

HTML [Ref] <LI>  (custom)       <LI><a href="%URL_HTMLIFIED%" Title="%TITLE_HTMLIFIED%">Ref</a>



WIKI ext <LI>                   *[%URL_HTMLIFIED% %TITLE_HTMLIFIED%]
*[http://battellemedia.com/ John Battelle's Searchblog]
*[http://blogs.nybooks.com/ NYRblog - The New York Review of Books]
*[http://jordychens.blogspot.com/ Blogger: Blog not found]

WIKI ext <LI> (with both)       * %TITLE_HTMLIFIED%<br>%URL_HTMLIFIED% 

_
TITLE and URL (spaced):     %TITLE%%EOL%%URL%%20%EOL%
John Battelle's Searchblog
http://battellemedia.com/

NYRblog - The New York Review of Books
http://blogs.nybooks.com/

Blogger: Blog not found
http://jordychens.blogspot.com/
_
JPG1 for SCPC thumbs:       <img src="%URL_HTMLIFIED%" Title="%TITLE_HTMLIFIED%" height="175px">
_
JPG2 for SCPC:              <p><img src="%URL_HTMLIFIED%" Title="%TITLE_HTMLIFIED%"><br>%TITLE%
_
Open in Tabs (prefix javascript:)      void(window.open('%URL_HTMLIFIED%'));
_
unesc + escaped test        %TITLE%%EOL%%DESCRIPTION%%EOL%%URL%%EOL%
_
all of new tokens            %AUTHOR%, %AUTHOR_HTMLIFIED%,  %DESCRIPTION%, %DESCRIPTION_HTMLIFIED%, %KEYWORDS%, and %KEYWORDS_HTMLIFIED% %EOL%--%TITLE% -- %URL%%EOL%  
_
<a href title=desc>title</a>  <a href="%URL_HTMLIFIED%" %EOL% Title="%DESCRIPTION_HTMLIFIED%">%TITLE%</a>%EOL%
_
<li> internal description    <li><a href="%URL_HTMLIFIED%" %EOL%  title="%DESCRIPTION%">%TITLE_HTMLIFIED%</a> </li>
_
<li> External description    <li><a href="%URL_HTMLIFIED%"><b>%TITLE_HTMLIFIED%</b></a>%EOL% <br>%DESCRIPTION%</li>
_
<a href title=title>title</a>,  <a href="%URL_HTMLIFIED%" Title="%TITLE_HTMLIFIED%">%TITLE%</a>,&nbsp; 
_
newtab (newpage) internal title  <a target="_blank" href="%URL_HTMLIFIED%" %EOL%  title="%TITLE_HTMLIFIED% -- %DESCRIPTION%">%TITLE_HTMLIFIED%</a>,&nbsp;
_
Evernote title/anchor/description to be processed   
                                 <p><a href="%URL_HTMLIFIED%"><b>%TITLE_HTMLIFIED%</b></a>%EOL% <br>%DESCRIPTION%%EOL%
_
_
   
_
    
        

...see https://support.mozilla.com/questions/851496
...Use to create a bookmarklet to open a list of urls into tabs, prefix result with "javascript:"
_
 


_=======================================================================

Requested Enhancement: 2010-11-14  (and it was added August 29, 2011)

It would be nice if I could also use the description

 TITLE/Description/URL    %TITLE%%EOL%%DESCRIPTION%%EOL%%URL%%EOL%

The addition of these properties (Meta tags) as seen in Tab Information
would be appreciated.

author
description
keywords
-=======================================================================