Samsung is now rolling out February 2019 security patch update for the latest Galaxy S9 and S9 Plus devices. This new update comes with some critical bug fixes and system performance improvements. According to users, this is by far the best update after Android 9.0 Pie based on OneUI. It features new firmware build numbers G960FXXU2CSB3 and G965FXXU2CSB3 for Galaxy S9 (SM-G960F) and S9 Plus (SM-G965F) respectively.
Users already running the February 2019 OTA update claim that the blur effect is now gone while pulling down the notification shades. Moreover, recent apps animation lag has been fixed as well. The overall firmware experience seems much smoother than before. Apps start much faster now. So this is a must have OTA update for all Samsung devices running One UI.
The update is currently rolling out in European region starting with Germany. Soon the update will roll out in the United States, Asia, and other European countries. The update comes to the stable channel and most of the S9 and S9 devices are already running Android 9 Pie. So you can simply go to Settings > System Updates > and Download OTA updates manually.
Alternatively, you can also download the full stock firmware using this tutorial. If your S9 device is still on Android 8.0 Oreo, then you can download the One UI full Odin firmware and flash it using latest Odin tool. The instructions are all listed there.