To cries of, “Finally!” from developers everywhere, Microsoft stopped supporting Internet Explorer 8, 9 and 10 on Jan. 12 as it continues to push users to migrate to the newer Edge browser.

Though IE 11 will continue to receive security updates and bug fixes, in addition to Edge, the move is one more step toward the grave for what the company now considers a “legacy browser.”

Those developers still worrying about how to support outdated versions of IE can now focus on IE 11 and Edge, which is faster, more intuitive and includes features like built-in note-taking and integration with Cortana. Rather than releasing multiple versions, Microsoft says it will simply update Edge automatically in Windows Update.

Edge still doesn’t support browser extentions, however. Some details of planned extensions—like Adblock Plus—have been leaked, but Microsoft hasn’t announced when those will be available to users.

Meanwhile, an estimated 340 million machines now running outdated versions could be left vulnerable to viruses and malware if their owners don’t upgrade to a newer browser. Yikes.

The change doesn’t cover certain enterprise server systems running older versions of IE, which Microsoft will continue to support. See a full list of supported browsers here.