The OxygenOS 11.2.5.5 update is reportedly rolling out to the Indian variant of OnePlus 9 and 9 Pro. But, it should reach other regions pretty soon. The update improves HDR effect in some shooting scenes, white balance performance of the rear camera, network stability, Wi-Fi connection performance, system stability, and charging performance. The list of fixes in the latest update includes the keyboard lagging issue and some other known issues which are not detailed in the changelog. As usual, the update should be rolling out in an incremental fashion, which means that it will reach a small percentage of OnePlus 9 and 9 Pro users. After this, the company rolls out the update to the remaining devices, after confirming that no critical bugs are present. To manually check for the latest update navigate to Settings » System » System updates.
OnePlus 9 and 9 Pro OxygenOS 11.2.5.5 Update: Changelog
System
Improved charging performance Fixed the small probability lagging issue of the keyboard Fixed known issues and improved system stability Updated Android security patch to 2021.05
Camera
Improved the HDR effect in some shooting scenes Improved the white balance performance of the rear camera
Network
Improved the stability of network communication Improved the performance of Wi-Fi connection
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