i_manish , via OnePlus 6 Mirror Black , Jan 24, 2021 : 1. Goto Settings > Buttons & gestures > Navigation & bar. 2. Choose all the navigation bars randomly untill you get the different navigation icon. 3. For navigation bar option - (Back, home and recents) showing up two different behaviour icons. On selecting this option I am seeing this when choose randomly between three options. Below are the screenshot for the same. Please look into this.