OxygenOS from OnePlus provides a heavily customized Android experience and a variety of useful features and options. For example, you can find a built-in "Pocket mode" in OxygenOS that prevents accidental touches when the device is kept inside your pocket. However, a toggle to disable this particular option is apparently missing on devices like the OnePlus 7 and the OnePlus 7 Pro after the most recent OxygenOS update.

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The OnePlus 7 family recently received OxygenOS 10.3.3 (OxygenOS 10.0.6 for the European variants) that bumped the Android security patch level to May 2020 and brought in features like Dolby Atmos support for the new OnePlus Bullets Wireless Z earphones. Open Beta users, on the other hand, got the same security patch level in the form of Open Beta 14 a few days before the stable channel rollout. It might be a coincidence, but the "Pocket mode" toggle under Settings > Utilities seems to be missing right after these updates.

Although the toggle is visually absent, the pocket mode detection algorithm is always running in the background. It eventually breaks ambient display-related features like double-tap to wake and pickup to show in low light conditions, because the phone believes that it is still in your pocket. Due to the fact that OnePlus tends to re-use a majority of the UI codebase of OxygenOS across their devices, the glitch may affect non-OnePlus 7 (Pro) phones as well.

Hopefully, there is an easy way out, but you have to be rooted in order to apply the fix. All you need to do is add the following text snippet to the end of /system/etc/feature_list file on your phone (just before the last ]).

        ,
   {
       "featureName": "OP_FEATURE_ENABLE_POCKETMODE_SWITCH"
   }

Reboot the phone after saving the changes and the "Pocket mode" toggle should now be visible under Settings > Utilities. Note that the default status of the option should be "disabled" after adding the above code, thus you may need to toggle it twice to properly turn off pocket mode detection.


Source: OnePlus Forums