ニコ生 resizer is a Chrome add-on developed by tkawachi. It falls under the category of Browsers and specifically the subcategory of Add-ons & Tools. The program is designed to resize the player for Nico Nico Live, a popular live streaming platform in Japan.

With the discontinuation of the flash version player, the need for this extension has been eliminated. As a result, the functionality provided by ニコ生 resizer is no longer necessary.

Overall, ニコ生 resizer was a useful tool for resizing the player on Nico Nico Live. However, due to the changes in the platform's technology, it is no longer relevant or needed. Users are advised to refer to the official announcement for more information on the discontinuation of the flash version player.