From MozillaZine Knowledge Base

These instructions are for Windows only, other systems will vary

Most Laptop touchpads have a feature allowing you to drag your finger down the side or along the bottom of the pad to quickly control scrollbars. However, this feature may not work in Firefox or Thunderbird if they are not supported by the driver that shipped with the system.

Synaptics

You can solve this problem by obtaining the latest driver for your touchpad from your manufacturer. Synaptics provides a standard driver which works for many laptops, but it will not have the same features as the manufacturer's driver. You can check if your touchpad will support Synaptics' driver by looking for Synaptics TouchPad in the Windows Device Manager.

Download the latest driver from Synaptics here: http://www.synaptics.com/support/drivers

An Acer computer user apparently reports that he didn't get it working with the above synaptics driver but did with a dell driver.

Many users find that the driver will work after you download it a second time from the manufacturers support page.

Alps

The back and forward functions don't work with Alps driver. There is a workaround by changing the title of the program to Netscape using the Titlebar Tweaks extension (or manually modifying the title). Another workaround involves editing the hex values in apoint.exe. Both methods are described here.

Lenovo / IBM Trackpoint

See suggestion by "Lozang" at http://forums.mozillazine.org/viewtopic.php?f=38&t=303656