Firefox 4 adds speed and tames your tabs

You can then put those tabs in groups -- a social networking group, a news group, an entertainment group and a technology group, for example.

Drag any tab out of the box, and Panorama creates a new tab group. Drag another tab out of the box and place it on top of the first tab that you dragged out, and those tabs form their own tab group in their own box. You can keep creating new groups this way. You can also drag a tab from one group to another.

Double-click any of those groups in Panorama, and you go back to normal Firefox -- but the only tabs visible are those in that group; the tabs in the other groups are hidden. Go back to Panorama, click on a different group, and you'll be working with only those tabs. When you browse the Web and add new tabs, the tabs get added to whatever tab group you're currently using.

Panorama includes a lot more features, including the ability to close tab groups, resize them and rename them. You can also perform a limited search of all of your open tabs. Panorama will search only the URLs and titles of open tabs, not the content on the pages themselves, but still, it's a useful little feature.

There's so much to Panorama that it will likely take some time to get used to. But if you're a frequent user of multiple tabs, you'll never want to give it up.

More tab-taming

Firefox 4 introduces another feature, called Switch to Tab, to help you tame your tabs. As in the previous version of Firefox, when you type text in the address bar, Firefox searches through your history, previous searches and sites you've bookmarked and shows likely matches in a drop-down list below the address bar. Now, however, it also searches through any tabs you have open.

If it finds any matches in your open tabs, it shows a "Switch to tab" icon below the Web page's title in the drop-down list. To go to the tab, click the icon. As with Panorama, this feature searches only the URLs and words in the titles of open tabs, not the content of the sites themselves.

Although the feature is useful, it could be improved. Any search results that match open tabs get mixed in with your history list, previous searches and so on. So it's difficult to see at a glance if your matches are in open tabs.

In addition, you may get multiple matches for the same Web page. If you type "cn" into the address bar, for example, and you have CNN.com open, you may see two matches for it: one from your history list, and another showing it's an open tab. Switch to Tab would be more useful if it showed matching tab search results separately -- on the top of the list, perhaps.

With Firefox 4, you can also permanently pin a tab to the left of the tab bar. That way, the tab is always there, even when you restart Firefox. It's a moderately useful feature, but doesn't go as far as similar Chrome or Internet Explorer features, both of which also let you pin tabs. In Chrome you can also create a shortcut on your desktop to launch a site, while in Internet Explorer 9 you can pin a site to your taskbar in Windows 7.

Firefox Sync

If you use Firefox on different computers, operating systems and/or devices, you'll be pleased with Firefox Sync, introduced in this new version. Firefox Sync can synchronize bookmarks, browsing history, passwords and open tabs.

If you use Firefox on a Mac and a PC, for example, Firefox Sync will automatically keep all of that in sync between them. And it will also work with the Firefox mobile browser, currently in beta. To do this, you'll have to first set up a Firefox Sync account, and then follow the instructions for using multiple devices. It's a simple and straightforward process.

You can even simultaneously display open tabs from another computer running Firefox. You click the Down arrow at the right of all of your open tabs and select "Tabs from other computers," and you'll see a listing of all of your open tabs on another computer or device. Double-click any of them to open it.

But the tab-sharing feature can be confusing to use. If you are displaying the tabs from another computer, and new tabs are added or closed on the other computer, your display won't update -- it will only show the tabs that were open at the time you asked to see them. In order to see the currently opened tabs, you have to close the page and then ask to see the tabs from another computer again.

Firefox Sync is not completely new to Firefox. In 2007, Mozilla began a syncing project called Weave that is available as an add-on to previous Firefox versions as well as for iPhones, BlackBerry phones and as a beta for Android phones. However, with Firefox 4, it's baked directly into the browser for the first time.

Firefox Sync may not be that useful to those who use different browsers. For them, a better bet is Xmarks, which synchronizes browser bookmarks and passwords for Firefox, Safari, Internet Explorer and Chrome.