Unified Back-/Forward Button provides a double-button with just one menu for navigating back and forward:

Slightly outdated screenshot

The features of this extension are:

Download

Unified Back-/Forward Button 0.6 [released 2007-08-25]

This release works for Firefox 2.0 (mainly tested with the Winstripe theme).

Note: Parts of this extension have been integrated into Firefox 3.0, so there won't be another update.

Customization

The maximum length of the unified menu can be changed by creating a new Integer pref called browser.sessionhistory.unified_length in about:config and setting it to a value different than 11 (the default).

Styling

The button could be styled further through userChrome.css. E.g. to make it easier to hit with the mouse:

/* Fitts' Back Button - bigger target on the icon-only toolbar */
toolbar[mode="icons"] #back-button > [anonid="button"] {
   -moz-box-orient: horizontal !important;
}
toolbar[mode="icons"] #back-button > [anonid="button"] > label {
   display: -moz-box !important;
   margin: 0px 2px 1px 2px !important;
   -moz-margin-start: 5px !important;
}

And if you prefer the history to be ordered in reverse (earlier visited entries at the top):

/* Order the drop-down menu in the same way as the Forward button's menu */
#back-button[unified] > menupopup scrollbox > box {
   -moz-box-direction: reverse !important;
}

Accessibility

Back and Forward are as usual [Alt]+[Left] and [Alt]+[Right]. To access the drop-down menu, you can use the following keyconfig macro ([Esc] closes the menu):

document.getElementById("back-button").open = true;

Revisions

Current: version 0.6
After the update, you might have to move the two buttons provided by Firefox to where the combined button used to be. Also any further customization through userChrome.css will have to be adapted.
The original Back and Forward buttons are merged now (a separate button is no longer provided).
The button parts can be individually added/removed from the toolbars.

Version 0.5
Updated for Firefox 2.0
Version 0.4.5
Reversed the page list order (last to first)
Reduced the default list length to 11
Version 0.4
Dropped support for specific themes in favor of a solution which should look OK with most themes
Version 0.3.4
Supports also miniFox, miniFoxFlat, iFox, iFox Graphite, iFox Orange
Version 0.3.3
The last history entry can now also be reached through fast-forward
Version 0.3.2
Clicking on a disabled button acts as if clicking on the dropdown marker
Version 0.3.1
Bug fix: clicking on the disabled button resulted in an empty popup menu
Version 0.3
Bug fix: an entry could appear both as a normal and as a fast-forward entry
Version 0.2.2
Supports the following themes: Qute, Noia (Extreme), Apollo, Safire, Eternal Aqua, iFox Smooth
Version 0.2.1
Highlight the active page additionally with a bullet
Version 0.2
Added fast-rewind/-forward menu items (inspired by this 'Places' draft)
Made the menu length customizable through about:config (extensions.unibafo.*)
Version 0.1
Initial release 2006-03-06
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