Your Pixel 2 XL may have display issues.
The plastic-substrate based OLED displays on the new Google Pixel 2 XL seem to be coming with an unwanted feature: Permanent navigation buttons.
Highlighted above in the augmented circles, (photo credit Alex Doboe; empashis mine) it seems that the Pixel XL has numerous reported issues of burned-in nav buttons at the bottom of the screen. This seems to be an issue on the Pixel 2 XL exclusively.
According to Google:
The Pixel 2 XL screen has Been designed with an advanced POLED technology including QHDplus resolution, wide color gamut, and high contrast ratio for natural and beautiful colors and renderings. We put all of our products through extensive quality testing before launch and in the manufacturing of every unit. We are actively investigating this report.
The Video How-To
The following video will outline in visual detail, the issues you may be experiencing and how to check:
Also published on Medium.