If you find your 'Yahoo toolbar missing’ in Mozilla Firefox,' you may reinstall it by following the steps below. By choosing "Add-ons" found in Firefox menu bar, you may access the Add-ons Manager. Firefox includes the Yahoo Toolbar in its list of installed add-ons. The list only includes active and deactivated add-ons; uninstalling an add-on permanently removes it from the system. The alternative is as follows. To reactivate the Yahoo Toolbar, locate it in the list of installed add-ons and select the "Enable" option. Prior to actually reinstalling the toolbar, it's a good idea to remove it first. Reload your Web browser to apply the changed settings. If the add-on was previously removed, reinstall it.