Mozilla has advised Firefox customers not to try add-ons classed as “experimental,” such as the recently released China Channel, because they could cause computer problems. Firefox add-ons allow users to personalize their browsing and add additional features, and because Firefox is open source, many of these add-ons are thought up by third-party developers. Add-ons classed as “experimental” are those still being tested, although they are available for public use. However, Mozilla does not recommend users downloading such add-ons unless they are very technically minded.

Mozilla Cautions Against Experimental Firefox Plug-Ins