The number of Firefox extensions continues to grow. For example, when I last wrote about tab extensions just over a year ago, about 110 existed. Now, despite the need to rewrite many extensions to make them compatible with Firefox 3.0, the number is over 190, and the choice is greater than ever. Basic functionality, coloring options, positioning of the tab bar, automatic opening of tabs at startup -- whatever your need, you can probably find it on the Firefox add-ons site.
By far the largest number of tab extensions add an item or two to Firefox's defaults. Open Link in..., for example, simply adds the ability to choose whether to open new links in background or foreground tabs or windows. Another small addition is Tab History, which allows new tabs to inherit the history of their parent tabs, thus saving you the need to click back on the parent to retrace your steps.
Group/Sort Tabs is slightly more ambitious. It groups tabs by host names, or order of opening or browsing. It also lets you set a gap between each group of tabs. It can be especially effective if combined with one of the extensions that color-codes tabs (see below).
By contrast, Informational Tab is less successful. It tries to improve tabs by adding a progress bar for the opening of the page, a well as a thumbnail of the page and a close button on each tab. The progress bar and close button work reasonably well, but the thumbnail is too small to be of use -- even if you adjust the default, tabs are simply too small for viewable thumbnails.
More successful modifications are Find in Tabs and Print All Tabs, whose purposes should be self-explanatory from their names. Print All Tabs require that you use a little care and close the pages you don't want to print, but Find in Tabs is ideal for research. It adds an option to Firefox's default Find pane, and prints results to a sub-window in which hits are identified by tab number counted from the left, or by the favicon or mini-icon associated with the page on which the hit appears.
Perhaps the most original extension of basic functionality is Tab Splitter, which allows you to split the Firefox window horizontally or vertically to display two separate pages at once. For some reason, the second pane has its own set of navigation buttons, which are different from Firefox's default ones, but the ease of comparing separate pages is so great that Tab Splitter is almost as much an improvement over default tabs as tabs are over untabbed browsing.
Coloring tabs is a popular idea in Firefox add-ons. You can use Aging Tabs to gradually change the color of tabs as they stay open, tying the change in color to the last time you viewed each tab, or to the time it was opened. You can also take the opposite approach with ColoUnREaDTabs and highlight tabs that you haven't got around to viewing yet.
Should you want to color-code tabs according to a scheme of your own, try FlagTab. With this extension, you can manually apply a color to a tab from the right-click menu, and add a category name to each color. The only real problem with this extension is that you are limited to four colors; I can easily envision using 10 or more when doing large research projects.
In earlier versions of Firefox, one of the most popular extensions was ChromaTabs, which tried to assign a color appropriate to each Web page. ChromaTabs Plus is currently being developed for Firefox 3.0, but, if you are cautious, you might prefer to use Colorful Tabs instead. It gives to each open tab a different color that, as with Aging Tabs, fades with the amount of time that the tab has been opened. It also include an option for using a background image on each tab. The extension works well, but advocates of computer freedom might want to avoid it, because Colorful Tabs' two-line license is clearly a proprietary one.
Repositioning the tab bar
One extension that I've missed since the release of Firefox 3.0 is Vertigo, which in older versions of Firefox opened tabs in a vertical list rather than a horizontal one. A vertical list has the advantage that you can adjust the size to display the complete title of each page, and you can arrange pages in a tree, with child links directly under parents.
Tree Style Tab resurrects these advantages, with a wide array of options to change both the appearance and behavior of tabs as you open and close them, as well as the context menu's contents and any auto-hide behavior for the tab pane. Some especially useful options are the ability to position the tab pane on any side of the browser window, and an option to open new pages automatically in new tabs without specifying this behavior each time. You can also close all the pages in a sub-tree together, or specify that child pages stay open when you close their parent.
You can find similar functionality in VertTabbar, an extension that is still in development.
When you go online every day, chances are that the first thing you do is visit the same blogs, comics, or news sites. You can automate the process by arranging bookmarks in folders and selecting "open all" in tabs from each folder's context menu, but the process can still be repetitive.
An even more automated solution is Morning Coffee, which allows you to open bookmarks automatically when you open Firefox. You can choose the bookmarks you open every day, as well as the ones that you open on particular days, which can save you the trouble of clicking through comics or blogs that only publish on certain days of the week. If you choose, you can randomize the order in which the bookmarks of the day open, just to give yourself some variety. Much the same functionality is available in the experimental Daily Bookmarks.
The trouble with Morning Coffee is that setting it up can be time-consuming if you have several dozen bookmarks to schedule. It can also be a nuisance if Firefox crashes and you have to restart your browser.
No recent tab extensions combines all the features mentioned here, but Tab Kit comes close. With Tab Kit, you can have a horizontal or vertical tab bar, group tabs, color-code them as unread, current, or protected, and fine-tune each behavior with a number of different options.
For instance, if you have a horizontal tab bar, you can set it to use multiple rows, which allows you to see more tabs before you need to scroll. By contrast, if you choose a vertical tab bar, you can define how far each child tab is indented from the parent. As for individual tabs, you can set a standard width for them, and set whether they have close buttons. Should you get confused with all the options, the Preferences dialog for the extension in Tools -> Add-ons has a Reset button to return Firefox to the default state without uninstalling the extension.
As with most Firefox extensions, the problem with tab extensions is potential incompatibility with each other. Enabling Tree Style Tabs, for instance, disables Tab History. The more extensions you add, the greater the odds of some incompatibility. Expecting all extension writers to test their work against other add-ons is probably unrealistic, but the effort sometimes required in troubleshooting can quickly make you wish that other extensions would include Find in Tabs' option to check for compatibility each time that Firefox starts. However, until they do, the more extensions you use, the more likely you'll encounter some problems.
Such annoyances aside, Firefox tab extensions are obviously thriving. It's not just a case that if something to suit your needs isn't available now it probably will be next week -- it's more a case that if you browse what's available, you'll discover all sorts of essential add-ons that you hadn't previously imagined.
Every Monday we highlight a different extension, plugin, or add-on. Let us know if you have one to suggest.