Yes, this is a real sentence being written in 2021: Two new maps are set to be added to Halo 3 in the season six update to the Halo Master Chief Collection.
Back in 2015, 343 Studios began collaborating with Saber Interactive on a multiplayer-only version of Halo titled Halo Online. A closed alpha version of Halo Online was released in Russia, where Saber is located, in April 2015. But the game was inevitably canceled in August 2016.
Fast forward to over four years later and Halo fans will get their armor-clad hands on two Halo Online original maps that will now be added to Halo 3 as part of the Master Chief Collection. Waterfall and Edge (not the browser) will release with season six, along with a plethora of armor and accessory customization options for Halo 3.
Dedicated fans of the series who are a part of the Halo Insider Program got to preview the new maps in February and were blown away by how beautiful they looked. The last time Halo 3 got new maps was in 2009 with the Mythic II Map Pack. Players could purchase the pack for 800 Microsoft points or get the Halo 3: Mythic disc that came with copies of ODST. But for MCC players today, the new maps are free additions.
Halo MCC season six is expected to be released in March.