Facebook's chat functionality will no longer be supported on Internet Explorer 6 after September 15, the social-networking site announced Wednesday.

In order to improve chat performance, Facebook plans to upgrade its system in the coming weeks and improve "the way connections are established and messages are sent," the company said. Some of the bigger improvements, however, are not supported on older browsers like IE6, so starting next month, chat will no longer work on that version.

One of the major complaints about chat was its tendency to cut out mid-conversation or just stop working altogether. "We're working hard to end those interruptions so that your experience is stable and consistent," Facebook said in a blog post.

According to July data from Net Applications, IE6 is the second most popular browser, with 16.97 percent of global market share behind IE8, which has 26.87 percent. Those versions are followed by Firefox 3.6 with 16.15 percent, IE7 with 11.43 percent, and Chrome 5.0 with 6.48 percent.

Users running IE6 can upgrade on Microsoft's Web site.